Hyponatremia

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RxDrug of choice3% hypertonic saline (for severe symptomatic hyponatremia); oral urea 30 g/day (for chronic SIADH)

AltAlternativesTolvaptan 15-60 mg/day (vaptan); empagliflozin 25 mg/day (SGLT2 inhibitor); desmopressin (for overcorrection rescue)

⊘AvoidThiazide diuretics in hyponatremic patients; vaptans in hypovolemic hyponatremia and liver disease; non-dihydropyridine CCBs (no direct role, but avoid in heart failure)

DxTest of choicePlasma osmolality, spot urine osmolality and urine sodium, volume status assessment (including PoCUS)

ScKey scoreSHOR score (Severe Hyponatremia Overcorrection Risk) to predict rapid correction; MELD-Na for liver disease prognosis

→When to referPersistent or severe hyponatremia (Na <120 mEq/L), suspected adrenal insufficiency, need for dialysis, ODS, or unclear etiology

Hyponatremia is common and dangerous; management hinges on accurate volume status and controlled correction (≤8 mEq/L/24h in chronic cases) to prevent osmotic demyelination.

Hyponatremia, defined as serum sodium <135 mmol/L, is the most common electrolyte disorder in hospitalized patients, affecting up to 47% of admissions in some populations. It independently increases mortality, fracture risk, and neurocognitive deficits, yet it is often underrecognized. Management hinges on accurate volume status assessment and controlled correction to prevent osmotic demyelination syndrome (ODS). First-line therapy for severe symptomatic hyponatremia is 3% hypertonic saline; for chronic euvolemic hyponatremia, fluid restriction and oral urea are preferred. Vasopressin receptor antagonists (vaptans) and SGLT2 inhibitors are second-line options. The key to safe management is limiting the 24-hour sodium rise to ≤8 mEq/L in chronic cases.

Overview and Recommendations

Background

•Hyponatremia (serum sodium <135 mmol/L) is the most common electrolyte disturbance among hospitalized patients, affecting up to 47% of admissions in cancer centers and 6.9% of community-dwelling adults. It is independently associated with increased morbidity and mortality across diverse clinical settings, including heart failure, cirrhosis, and chronic kidney disease.
•Classification by duration (acute <48 hours, chronic ≥48 hours) and severity (mild 130-135, moderate 120-129, severe <120 mmol/L) guides management. Volume status, hypovolemic, euvolemic, or hypervolemic, is the cornerstone of diagnostic classification and dictates treatment. Key causes include (euvolemic), renal salt wasting (hypovolemic), thiazide diuretics, heart failure, cirrhosis, and adrenal insufficiency.
•Pathophysiology centers on impaired renal water excretion due to persistent arginine vasopressin (AVP) secretion despite hypotonicity. In health, plasma osmolality <285 mOsm/kg suppresses AVP; in hyponatremia, baroreceptor-mediated or ectopic AVP release sustains water reabsorption via aquaporin-2 channels in the collecting duct. The brain adapts to chronic hyponatremia by exporting organic osmolytes over 48-72 hours, rendering it vulnerable to osmotic injury if correction exceeds 8 mEq/L in 24 hours, the mechanism behind (ODS).
•Epidemiology: prevalence is 6.9% in the community (Dallas Heart Study) and up to 47% in hospitalized cancer patients. Women have twice the rate of severe hyponatremia compared with men, and the elderly are disproportionately affected due to age-related declines in urinary dilution and polypharmacy. Thiazide diuretics confer a 5-fold risk (HR 4.95), and second-generation antidepressants increase 30-day hospitalization risk by 5.46-fold. High ambient temperature (>20°C) markedly increases prevalence in those >80 years.
•Key syndromes: (euvolemia, urine osmolality >100 mOsm/kg, urine sodium >40 mmol/L, low uric acid); renal salt wasting (hypovolemia, high urine sodium, persistent hypouricemia after correction); thiazide-associated hyponatremia (older age, female sex, low BMI, often with hypokalemia); and primary polydipsia (urine osmolality <100 mOsm/kg). Accurate differentiation is critical because treatment is opposite: fluid repletion for hypovolemia versus fluid restriction for SIADH.

Evaluation

•Suspect hyponatremia in any patient with headache, nausea, vomiting, confusion, seizures, or coma, especially if on thiazides, SSRIs, or with underlying heart failure, cirrhosis, or malignancy. Even mild chronic hyponatremia (130-135 mmol/L) can cause subtle gait instability and cognitive impairment, increasing fall risk.
•Confirm hypotonic hyponatremia by measuring plasma osmolality: <275 mOsm/kg confirms hypotonicity. If osmolality ≥295 mOsm/kg, consider hypertonic hyponatremia (hyperglycemia, mannitol); if 275-295, consider pseudohyponatremia from hyperlipidemia or paraproteinemia.
•Assess extracellular fluid volume status through history (orthostasis, vomiting, diarrhea, edema), physical exam (jugular venous pressure, skin turgor, mucous membranes, edema), and consider point-of-care ultrasound (lung B-lines, IVC collapsibility, VExUS score) to improve accuracy over exam alone.
•Order spot urine osmolality and urine sodium before any therapy. Urine osmolality <100 mOsm/kg suggests primary polydipsia or low solute intake (beer potomania); >100 mOsm/kg indicates inappropriate ADH activity (SIADH, hypovolemia, hypervolemia).
•Interpret urine sodium: <30 mEq/L suggests hypovolemia (extrarenal losses) or hypervolemia (heart failure, cirrhosis); >30 mEq/L suggests SIADH, renal salt wasting, diuretic use, or hypocortisolism. Caveat: diuretics can elevate urine sodium regardless of volume status.
•Measure serum cortisol (8 AM) and TSH to exclude adrenal insufficiency and hypothyroidism. Low cortisol with high ACTH suggests primary adrenal insufficiency; low cortisol with low/normal ACTH suggests secondary. Hypothyroidism is an uncommon cause but should be ruled out.
•Consider fractional excretion of urate (FEurate) to differentiate SIADH from renal salt wasting: in SIADH, FEurate is elevated during hyponatremia but normalizes after correction; in RSW, it remains persistently elevated. Hypouricemia is present in ~70% of SIADH patients.
•In unclear cases, plasma copeptin (surrogate for AVP) measured after hypertonic saline infusion (target Na ≥150 mmol/L) can distinguish primary polydipsia from partial central diabetes insipidus with high accuracy (96.5%), though not yet routine.
•Imaging: chest CT to screen for causing SIADH; brain MRI if CNS pathology suspected (e.g., multiple system atrophy, pituitary lesions). Adrenal CT if primary adrenal insufficiency from infection or malignancy is considered.
•Diagnostic criteria for SIADH (Bartter-Schwartz): euvolemia, plasma osmolality <275 mOsm/kg, urine osmolality >100 mOsm/kg, urine sodium >40 mmol/L, normal thyroid and adrenal function, no recent diuretic use. Reset osmostat is a variant where ADH secretion is regulated at a lower set point.
•Red flags requiring urgent intervention: respiratory compromise (PaO2 <70 mm Hg), autonomic instability (hypotension, bradycardia), seizures, or coma. These mandate immediate hypertonic saline and ICU admission.
•Common pitfall: misclassifying hypovolemic hyponatremia as euvolemic SIADH. A spot urine sodium <30 mEq/L with clinical signs of volume depletion should prompt volume repletion, not fluid restriction. Always check volume status before diagnosing SIADH.

Management

•For severe symptomatic hyponatremia (seizures, coma, respiratory arrest): administer 3% hypertonic saline IV, 100-150 mL bolus over 20 minutes; repeat every 20 minutes until symptoms improve or serum sodium rises by 4-6 mEq/L. Goal is to abate symptoms, not normalize sodium. Monitor sodium every 2 hours.
•For acute hyponatremia (<48 hours duration): can correct more rapidly; target 1-2 mEq/L per hour until symptoms resolve, then slow correction. The risk of ODS is low because brain adaptation has not occurred.
•For chronic hyponatremia (≥48 hours or unknown duration): limit correction to ≤8 mEq/L in the first 24 hours and ≤18 mEq/L in 48 hours. In high-risk patients (alcoholism, liver disease, malnutrition, hypokalemia), consider even stricter limits (≤6 mEq/L in 24 hours).
•Monitor serum sodium every 2 hours during active correction, then every 4-6 hours once stable. Use point-of-care testing if available. Document the rate of correction in the medical record.
•If overcorrection occurs (rise >8 mEq/L in 24 hours): re-lower serum sodium by administering desmopressin (DDAVP) 1-2 mcg IV or SC and 5% dextrose in water (10 mL/kg over 1 hour). This can reduce sodium by 2-9 mEq/L. Consider minocycline 200 mg orally twice daily for 5 days to prevent ODS (animal data, limited human evidence).
•For asymptomatic or mildly symptomatic euvolemic hyponatremia (SIADH): first-line therapy is fluid restriction ≤1 L/day. Assess adherence and response after 24-48 hours. If sodium does not rise by ≥2 mEq/L, consider adding pharmacotherapy.
•Add oral urea 30 g/day (range 15-60 g) in divided doses, mixed with flavored liquid or juice to improve palatability. Urea increases sodium by ~8 mEq/L on average, with overcorrection in only 3% of cases. It is inexpensive and well-tolerated long-term.
•Second-line: vasopressin V2-receptor antagonists (vaptans). Start tolvaptan 15 mg orally once daily; titrate to 30-60 mg based on response. Monitor sodium every 6-8 hours for the first 24 hours. Avoid in hypovolemic hyponatremia and in patients with liver disease (risk of hepatotoxicity). Limit use to 30 days due to cost and safety concerns.
•Alternative: empagliflozin 25 mg daily (SGLT2 inhibitor) for SIADH. In trials, it increased sodium by 4-10 mmol/L over 4 days and improved cognitive scores. No hypoglycemia or hypotension reported. Emerging evidence; not yet guideline-endorsed.
•For hypovolemic hyponatremia: replete volume with isotonic saline (0.9% NaCl) or balanced crystalloid (e.g., Plasma-Lyte). Correct the underlying cause (discontinue diuretics, treat vomiting/diarrhea). Monitor sodium and potassium; hypokalemia often coexists and should be corrected simultaneously.
•For hypervolemic hyponatremia (heart failure, cirrhosis): treat the underlying condition with loop diuretics, fluid restriction, and sodium restriction. Consider vaptans only if refractory and in patients without liver disease (tolvaptan is FDA-approved for hypervolemic hyponatremia but contraindicated in cirrhosis due to hepatotoxicity).
•Avoid thiazide diuretics in patients with hyponatremia; discontinue if they are the suspected cause. Thiazides impair urinary dilution and can cause severe hyponatremia, especially in elderly women with low BMI.
•In dialysis patients with severe hyponatremia: use concurrent dialysate flow (blood and dialysate flow in same direction) to slow correction, or use continuous venovenous hemofiltration (CVVH) with low-sodium replacement fluid. Monitor sodium every 2-4 hours; aim for rise <8 mmol/L in 24 hours. Avoid citrate-based anticoagulation if rapid correction is a concern.
•For drug-induced hyponatremia (SSRIs, carbamazepine, TMP/SMX, etc.): discontinue the offending drug if possible. If the drug cannot be stopped (e.g., essential antidepressant), manage with fluid restriction and consider switching to an agent with lower risk (e.g., mirtazapine).
•When to refer: to nephrology for persistent or severe hyponatremia (Na <120 mEq/L), recurrent hyponatremia, or if dialysis is needed; to endocrinology if adrenal insufficiency or hypothyroidism is suspected; to oncology if SIADH from malignancy is suspected; to neurology if ODS develops.
•Discharge criteria: serum sodium >130 mEq/L and stable for 24-48 hours, symptoms resolved, underlying cause identified and addressed, follow-up plan for monitoring sodium and adjusting therapy. Educate patient on symptoms of hyponatremia and when to seek care.

Board Review — High Yield

•SIADH diagnostic criteria, euvolemia, plasma osmolality <275, urine osmolality >100, urine Na >40, normal thyroid/adrenal.
•Osmotic demyelination syndrome (ODS), occurs when chronic hyponatremia is corrected >8 mEq/L in 24 hours; risk factors: alcoholism, liver disease, hypokalemia, malnutrition.
•Thiazide-associated hyponatremia, 5-fold risk; elderly women with low BMI; often with hypokalemia and metabolic alkalosis.
•Renal salt wasting vs SIADH, RSW: hypovolemia, persistent hypouricemia after correction, high renin/aldosterone; SIADH: euvolemia, hypouricemia normalizes after correction.
•First-line for severe symptomatic hyponatremia, 3% hypertonic saline 100-150 mL bolus; goal is to raise Na by 4-6 mEq/L to abate symptoms.
•First-line for chronic SIADH, fluid restriction ≤1 L/day; add oral urea 30 g/day if inadequate response.
•Overcorrection rescue, desmopressin 1-2 mcg IV/SC + 5% dextrose in water; can lower Na by 2-9 mEq/L.
•Empagliflozin for SIADH, SGLT2 inhibitor; increases Na by 4-10 mmol/L; improves cognitive scores; emerging therapy.
•SHOR score, predicts overcorrection risk; includes decreased consciousness, vomiting, severe hypokalemia, hypotonic urine, volume overload, chest tumor, age, initial Na <110.
•Hyponatremia in heart failure, independent predictor of mortality (HR 1.90); treat with fluid restriction, loop diuretics, consider vaptans if refractory (avoid in cirrhosis).

Deep Dive — Evidence Details

Definition, Classification and Nomenclature

▸Hyponatremia is defined as serum sodium <135 mmol/L and is the most common electrolyte disorder in hospitalized patients.
▸Classification by volume status (hypovolemic, euvolemic, hypervolemic) is the essential first step in diagnosis and directs therapy.
▸Renal salt wasting (RSW) is a distinct entity from SIADH; it requires fluid repletion rather than restriction, and can be differentiated by persistent hypouricemia and elevated FEurate after sodium correction.

HY High Yield: Always assess volume status (clinical exam, urine sodium, serum uric acid) before choosing therapy, fluid restriction for SIADH but saline for RSW can be life-saving or life-threatening if misapplied.

Hyponatremia is defined as a serum sodium concentration below 135 mmol/L ^[6]^A1a. This derangement is the most common electrolyte disturbance among hospitalized patients, affecting up to of inpatients, and is independently associated with increased morbidity and mortality across diverse clinical settings ^[3]^B2a.

Synonyms and Abbreviations

The condition is also referred to as hyponatraemia (British spelling). Key syndromes that produce hyponatremia include the syndrome of inappropriate antidiuretic hormone (SIADH), cerebral salt wasting (CSW), now preferably termed renal salt wasting (RSW) ^[1]^D5, and the (ODS), a feared complication of overly rapid correction ^[11]^A1a.

Classification by Duration

Hyponatremia is classified as acute when it develops over <48 hours and chronic when present for ≥48 hours or when the duration is unknown ^[3]^B2a. This distinction is critical because rapid correction of chronic hyponatremia risks ODS, whereas acute hyponatremia can be corrected more rapidly without the same danger ^[11]^A1a.

Classification by Severity

Severity is stratified using serum sodium thresholds, though definitions vary across studies ^[11]^A1a:

Category	Sodium Range
Mild	130-135 mmol/L
Moderate	120-129 mmol/L
Severe	<120 mmol/L

Most guidelines define severe hyponatremia as <120 mmol/L, the threshold at which symptoms become frequent and urgent intervention is typically indicated ^[11]^A1a.

Classification by Volume Status

Volume status is the cornerstone of diagnostic classification and dictates treatment. The three categories are based on clinical assessment of extracellular fluid volume ^[1]^D5^[2]^C4:

Volume Status	Key Features	Common Causes
Hypovolemic	Low jugular venous pressure, orthostasis, dry mucous membranes	Diuretic overuse, vomiting, diarrhea, renal salt wasting (RSW)
Euvolemic	No signs of volume depletion or overload	SIADH, glucocorticoid deficiency, hypothyroidism, polydipsia
Hypervolemic	Edema, , elevated jugular venous pressure	Heart failure, cirrhosis, nephrotic syndrome

Nomenclature of Specific Syndromes

SIADH is characterized by euvolemia, serum osmolality <275 mOsm/kg, urine osmolality >100 mOsm/kg, and urine sodium >40 mmol/L ^[1]^D5^[2]^C4. RSW (formerly CSW) presents with hypovolemia, high urine sodium (>40 mmol/L), and high urine output; it is distinguished from SIADH by persistent and increased fractional excretion of urate after correction of hyponatremia, as well as elevated plasma aldosterone and low plasma renin in SIADH ^[1]^D5^[2]^C4^[13]^B3b. Accurate differentiation is essential because treatment is opposite: fluid repletion for RSW versus fluid restriction for SIADH ^[1]^D5^[2]^C4.

Pearl: When a patient with hyponatremia has a cerebral lesion, always check urinary sodium and volume status, do not assume SIADH; renal salt wasting requires saline repletion, not fluid restriction, and a trial of isotonic saline can differentiate the two ^[2]^C4^[13]^B3b.

Classification of Hyponatremia by Severity

Category	Sodium Range
Mild	130-135 mmol/L
Moderate	120-129 mmol/L
Severe	<120 mmol/L

Pathophysiology and Mechanism

▸Impaired renal water excretion due to non-suppressed AVP despite hypotonicity is the core defect in hyponatremia.
▸Brain adaptation via organic osmolyte loss protects against edema but creates vulnerability to osmotic demyelination upon rapid correction.
▸Multiple pathophysiologic pathways converge on reduced free water clearance: baroreceptor-driven AVP, inappropriate AVP secretion (SIADH), and tubular diluting defects (e.g., thiazides).

HY High Yield: In chronic hyponatremia, the brain's osmolyte adaptation is complete within 48-72 hours; after that, the risk of osmotic demyelination from rapid correction outweighs the risk of cerebral edema from the low sodium itself.

Having classified hyponatremia by serum osmolality, volume status, and duration, the clinician must understand the underlying mechanism: impaired renal water excretion driven by persistent arginine vasopressin (AVP) secretion despite hypotonicity ^[16]^D5^[48]^D5. In health, a fall in plasma osmolality below ~285 mOsm/kg suppresses AVP release, allowing the kidney to excrete a dilute urine. In hyponatremia, this suppression fails - whether from baroreceptor-mediated AVP release in volume-depleted states (heart failure, cirrhosis), ectopic production (SIADH), or drugs that stimulate AVP or mimic its action ^[16]^D5^[49]^D5^[50]^D5^[51]^D5. The result is sustained water reabsorption in the collecting duct, producing concentrated urine (urine osmolality usually >100 mOsm/kg) that dilutes the plasma ^[48]^D5.

The Renal Tubular Effector: Aquaporin-2 and the Collecting Duct

AVP binds the V2 receptor on principal cells of the collecting duct, initiating a signaling cascade that inserts aquaporin-2 (AQP2) water channels into the apical membrane, rendering the segment water-permeable ^[27]^D5^[58]^D5. The driving force for water movement is the medullary osmotic gradient generated by countercurrent multiplication. In SIADH, sustained AVP action maintains AQP2 expression, preventing the normal water diuresis that would correct the dilution. However, the kidney mounts a counterregulatory response: "vasopressin-escape" - a loss of AQP2 despite high circulating AVP, mediated by a partial epithelial-to-mesenchymal transition triggered by transforming growth factor β signaling ^[27]^D5. This escape phenomenon limits the severity of hyponatremia in chronic SIADH but is incomplete, and the serum sodium stabilizes at a new, low steady state ^[27]^D5.

Brain Adaptation and the Risk of Osmotic Demyelination

The brain adapts to chronic hyponatremia by exporting organic osmolytes (e.g., myo-inositol, taurine, glutamate) to reduce intracellular osmolality and avoid swelling ^[37]^D5^[41]^D5. This adaptive loss of osmolytes is complete within 48-72 hours of sustained hyponatremia, rendering brain cell volume nearly normal. The adaptation, however, comes at a cost: the brain becomes vulnerable to osmotic injury if serum sodium is corrected too rapidly. Rapid correction causes a sudden increase in extracellular osmolality, driving water out of brain cells. The primary target is the astrocyte, which undergoes apoptosis soon after rapid correction, disrupting the astrocyte-oligodendrocyte trophic network, triggering microglial activation, and culminating in demyelination - the (ODS) ^[45]^D5. The risk is highest when the daily correction exceeds 8 mEq/L in patients with chronic hyponatremia (duration >48 hours) ^[26]^D5^[31]^C4^[41]^D5.

Specific Pathophysiologic Pathways

Thiazide-associated hyponatremia (TAH): Thiazide diuretics impair urinary dilution by inhibiting the sodium-chloride cotransporter in the distal convoluted tubule, reducing solute delivery to the diluting segment ^[35]^D5. Additionally, they may stimulate AVP release through volume depletion and directly increase collecting duct water permeability via prostaglandin modulation ^[35]^D5. Risk factors include advanced age, female sex, and low body mass; genetic susceptibility has been identified ^[35]^D5.
Hypovolemic hyponatremia (including cerebral salt wasting): True volume depletion (e.g., from diuretics, vomiting) activates baroreceptor-mediated AVP release, overriding osmoregulation ^[1]^D5^[44]^D5. The distinction from SIADH rests on the presence of hypovolemia, but accurate volume assessment is notoriously difficult; radioisotopic determinations suggest that renal salt wasting (RSW) is more common than previously recognized, especially in neurosurgical patients ^[1]^D5. In RSW, a natriuretic factor (possibly brain natriuretic peptide) causes excessive renal sodium loss, leading to volume depletion and secondary AVP release ^[1]^D5^[44]^D5.
Drug-induced SIADH: Many drugs, including selective serotonin reuptake inhibitors (SSRIs), carbamazepine, and ecstasy (MDMA), stimulate AVP secretion or enhance its action at the collecting duct ^[19]^C4^[20]^C4^[50]^D5^[51]^D5^[58]^D5. Carbamazepine directly increases AQP2 expression and water permeability in the inner medullary collecting duct, explaining its antidiuretic effect in diabetes insipidus and its propensity to cause hyponatremia ^[58]^D5.

Pearl: The risk of osmotic demyelination is determined by the rate of serum sodium correction, not the absolute nadir value; in chronic hyponatremia, the brain's full osmolyte adaptation makes it vulnerable to even modest overcorrection, and the safe upper limit is <8 mEq/L in any 24-hour period ^[26]^D5^[31]^C4^[41]^D5.

Epidemiology, Etiology and Risk Factors

▸Hyponatremia affects 6.9% of community-dwelling adults and up to 47% of hospitalized cancer patients.
▸Thiazide diuretics (HR 4.95) and second-generation antidepressants (RR 5.46) are the most important drug-induced risk factors.
▸High ambient temperature, female sex, and age >80 years synergistically increase the risk of severe hyponatremia.

HY High Yield: Thiazide diuretics and SSRIs are the two most common drug classes causing hyponatremia; check serum sodium 2 weeks after initiation in elderly patients.

The reduced capacity for renal water excretion that underlies hyponatremia translates into a high prevalence across diverse clinical settings. In the community-based Dallas Heart Study, the sample-weighted prevalence of hyponatremia (serum sodium <135 mEq/L) was 6.9% ^[71]^B2b. Among hospitalized patients, rates climb dramatically: in a cancer center cohort, hyponatremia was present in 47% of admissions (mild in 36%, moderate in 10%, severe in 1%) ^[78]^B2b. The elderly are disproportionately affected because of age-related declines in urinary dilution, polypharmacy, and a higher burden of comorbid conditions that stimulate vasopressin ^[31]^C4.

Demographic and Temporal Patterns

Women experience twice the rate of severe hyponatremia compared with men, a disparity that becomes more pronounced with advancing age ^[86]^B2b. Black ethnicity was independently associated with hyponatremia in the Dallas Heart Study (OR not reported but adjusted analysis included) ^[71]^B2b. Seasonal variation is striking: in a Swedish cohort, the prevalence of severe hyponatremia (<125 mmol/L) rose in a near-linear fashion with ambient temperature up to 20°C and then increased markedly above that threshold; among individuals >80 years old, rates exceeded 100 days of hyponatremia per million person-days at temperatures >22°C ^[86]^B2b. Projections suggest that a 1°C rise in mean temperature by 2050 could increase the prevalence of severe hyponatremia by 66% ^[86]^B2b.

Risk Factors

Table 1 summarizes the major modifiable and non-modifiable risk factors with their effect sizes. Thiazide diuretics carry the highest risk among commonly prescribed drugs, with a hazard ratio of 4.95 for any hyponatremia and an 8-fold risk for moderate-to-severe cases ^[75]^B2b. Age and lower body mass index significantly amplify this risk, whereas sex and estimated glomerular filtration rate do not ^[75]^B2b. Second-generation antidepressants increase the 30-day risk of hospitalization with hyponatremia by 5.46-fold, corresponding to an absolute risk increase of 1.31% (95% CI 0.87%-1.75%) ^[67]^B2b. Syndrome of inappropriate antidiuresis (SIAD), the most common cause of euvolemic hyponatremia, is driven by malignancy, pulmonary disease, CNS disorders, and medications ^[84]^D5. Other important etiologies include cirrhosis with , heart failure, chronic kidney disease, and profound hypothyroidism or adrenal insufficiency. Exercise-associated hyponatremia, though uncommon (<2% of ultra-marathon finishers), remains a preventable cause of life-threatening cerebral edema ^[99]^D5.

Risk Factor	Odds Ratio / Hazard Ratio	Evidence Level
SIAD (malignancy, pulmonary, CNS)	Not quantified as single estimate	5 (expert review) ^[84]^D5
Cirrhosis (dilutional hyponatremia)	Not quantified as single estimate	5 (expert review) ^[110]^D5
Heart failure	Not quantified as single estimate	5 (expert review) ^[74]^D5
Age >65 years	Effect modification (risk multiplier) ^[75]^B2b	2b
Female sex	Rate ratio ~2 for severe hyponatremia ^[86]^B2b	2b (register-based cohort)
High ambient temperature	Prevalence ratio increases sharply >20°C ^[86]^B2b	2b

Special Considerations

In cancer patients receiving immune checkpoint inhibitors, any-grade hyponatremia occurs in 5.0% (95% CI 2.3%-11.9%) and severe (≥grade 3) in 5.5% (95% CI 3.1%-9.6%) ^[83]^B2a; endocrinopathies account for only 0.3% of severe cases ^[103]^B3b. Postoperative hyponatremia develops in up to 41% of patients after total joint arthroplasty, with abnormal preoperative sodium being the strongest predictor (OR up to 12.33) ^[114]^B2a. In peritoneal dialysis patients, hyponatremia (sodium <135 mEq/L) is associated with a 45% higher mortality (adjusted HR 1.45) compared with sodium 140-141 mEq/L ^[76]^B2b.

Pearl: Thiazide diuretics and second-generation antidepressants are the two most common drug classes causing hyponatremia, each conferring a ~5-fold risk; always check serum sodium within 2 weeks of starting a thiazide or SSRI in elderly patients.

Clinical Presentation

▸Acute hyponatremia (<48 h) causes cerebral edema with seizures and coma; chronic hyponatremia (>48 h) causes subtle cognitive and gait impairment.
▸Even mild hyponatremia (Na 125-135 mEq/L) is associated with increased mortality and falls.
▸Atypical presentations (adrenal insufficiency, eating disorders, genetic syndromes) should be considered when hyponatremia is unexplained.

HY High Yield: The Timed Up and Go test and Trail Making Test are sensitive for detecting hyponatremia-associated gait and cognitive impairment [123].

! Warning: Hypoxia plus hyponatremia is a medical emergency, intubate early and correct sodium by 4-6 mEq/L with hypertonic saline [72].

The clinical expression of hyponatremia is governed by the interplay between the rate of decline in serum sodium and the brain's capacity for osmotic adaptation. Acute drops (within 48 hours) overwhelm compensatory mechanisms, producing cerebral edema, whereas chronic hyponatremia (developing over >48 hours) allows brain volume regulation through osmolyte extrusion, often blunting symptoms, yet recent evidence reveals that even mild chronic hyponatremia carries measurable neurologic and skeletal consequences ^[41]^D5^[55]^D5^[123]^B2b.

Presenting Symptoms

Symptoms range from none to life-threatening. Acute hyponatremia (serum sodium <120 mEq/L) typically presents with headache, nausea, vomiting, and confusion, progressing to seizures, coma, and respiratory arrest if untreated ^[72]^D5^[130]^D5. Chronic hyponatremia (serum sodium 125-135 mEq/L) is often labeled asymptomatic, but prospective studies demonstrate subtle cognitive impairment, gait instability, and increased fall risk ^[41]^D5^[55]^D5. In the Dallas Heart Study, mild hyponatremia (median sodium 133 mEq/L) was associated with a 75% increased mortality risk (HR 1.75) ^[71]^B2b. Thiazide-associated hyponatremia may present acutely or after months of therapy, with risk modified by age and low body mass ^[35]^D5^[75]^B2b.

Neurological Examination Findings

The neurologic examination should assess mental status, cranial nerves, motor strength, reflexes, and gait. In chronic hyponatremia, the Timed Up and Go test is often prolonged, and Trail Making Test A/B times are increased ^[123]^B2b. Hippocampal vulnerability is suggested by volume changes on MRI and impaired long-term potentiation in animal models ^[41]^D5^[123]^B2b. Deep tendon reflexes may be hyperactive if cerebral edema is present. Papilledema is rare but indicates severe intracranial .

Phenotypic Variants

Variant	Key Features	Frequency
SIADH	Euvolemia, low uric acid, urine Na >30 mEq/L, low urea	Most common cause of euvolemic hyponatremia ^[84]^D5^[131]^D5
Renal salt wasting (RSW)	Hypovolemia, high renin/aldosterone, persistent after correction	Underrecognized; may occur without cerebral disease ^[1]^D5^[2]^C4^[44]^D5
Thiazide-associated	Older age, female sex, low BMI, often hypokalemia	HR 4.95 for hyponatremia vs. no thiazide ^[35]^D5^[75]^B2b
Adrenal insufficiency	Hyperpigmentation, hyperkalemia, low cortisol, ACTH stimulation abnormal	31.8% of -induced ^[135]^C4; also triamcinolone ^[128]^C4
Hypothyroidism	Myxedema, bradycardia, elevated TSH	Uncommon cause
Primary polydipsia	Low urine osmolality (<100 mOsm/kg), low urine Na	Common in psychiatric patients
Cancer-related	SIADH from , chemotherapy, or	Up to 15% of hospitalized cancer patients ^[21]^D5
Drug-induced	TMP/SMX, SSRIs, NSAIDs, ecstasy,	TMP/SMX mimics SIADH but with hypovolemia ^[115]^C4; ecstasy causes hypotonic hyponatremia via AVP release ^[50]^D5
Eating disorders	, bulimia; often with hypokalemia, hypophosphatemia	13% prevalence of hyponatremia; OR 3.20 for electrolyte abnormalities ^[134]^A1a
Genetic syndromes	21-hydroxylase deficiency, , lipoid CAH, mitochondrial disease	Rare; hyponatremia may be presenting sign ^[119]^B3b^[136]^C4^[137]^C4

Red Flags

Respiratory compromise (hypoxia, PaO2 <70 mm Hg) combined with severe hyponatremia mandates ICU admission and rapid correction ^[72]^D5. Autonomic instability (hypotension, bradycardia) suggests adrenal crisis or brainstem herniation. Seizures or coma require immediate hypertonic saline bolus ^[122]^D5^[130]^D5. The risk of osmotic demyelination rises when correction exceeds 8 mEq/L in 24 hours, especially in patients with hypokalemia, alcoholism, or malnutrition ^[92]^B2b^[116]^C4.

Atypical Presentations

Hyponatremia may be the presenting feature of otherwise occult disease. In a neonate with seizures, serum sodium of 88 mmol/L led to diagnosis of 21-hydroxylase deficiency and Gitelman syndrome ^[136]^C4. In adults, isolated hyponatremia can herald adrenal insufficiency from pembrolizumab ^[135]^C4 or triamcinolone injections ^[128]^C4. Eating disorders, particularly anorexia nervosa, carry a 13% prevalence of hyponatremia and increased odds of electrolyte abnormalities (OR 3.20) ^[134]^A1a. In malaria with AKI, hyponatremia triples mortality odds (OR 3.67) ^[81]^B2a. Mitochondrial disease (m.3243A>G) presents with hyponatremia in 14% of patients, often without elevated creatinine ^[119]^B3b.

Pearl: Chronic hyponatremia is never truly asymptomatic, assess gait and cognition in every patient, as correction improves both and may reduce fracture risk ^[41]^D5^[55]^D5^[123]^B2b.

Diagnosis and Workup

▸The diagnostic workup of hyponatremia follows a systematic algorithm: confirm hypotonicity, assess volume status, and interpret urine studies to identify the underlying cause.
▸Differentiation between SIADH and renal salt wasting is crucial because treatment differs (fluid restriction vs volume repletion); persistent hypouricemia and elevated fractional excretion of urate after correction suggest RSW [1,2].
▸Newer biomarkers like copeptin and bedside ultrasound may improve diagnostic accuracy, but current guidelines still rely on clinical assessment and basic lab tests [126,63].

Dx Diagnostic Essentials: The gold-standard diagnostic algorithm is the systematic approach recommended by the 2013 US and 2014 EU guidelines, involving hypotonicity confirmation, volume status assessment, and urine studies [126].

HY High Yield: A low fractional excretion of urate (<12%) after correction of hyponatremia suggests SIADH, whereas persistently elevated values >12% suggest renal salt wasting [1,2].

Clinical features determine the urgency of intervention, but establishing the precise cause of hyponatremia requires a systematic diagnostic approach anchored on biochemical and clinical assessment. The diagnostic algorithm recommended by the 2013 US and 2014 EU guidelines proceeds through three sequential steps: confirm hypotonic hyponatremia, assess extracellular fluid volume status, and interpret urine studies to identify the underlying mechanism ^[126]^D5.

Step 1: Confirm Hypotonic Hyponatremia

Measure plasma osmolality. A value < 275 mOsm/kg confirms hypotonic hyponatremia. If osmolality is ≥ 295 mOsm/kg, consider hypertonic hyponatremia (e.g., hyperglycemia, mannitol). If between 275 and 295 mOsm/kg, the hyponatremia is isotonic (pseudohyponatremia from hyperlipidemia or paraproteinemia) ^[120]^D5.

Step 2: Assess Volume Status

History and physical examination are the initial tools, but bedside point-of-care ultrasound (PoCUS) - combining lung, cardiac, and abdominal assessment including the venous excess ultrasound score (VExUS) - improves accuracy of volume classification over physical exam alone ^[63]^B2a. Hypovolemic hyponatremia shows signs of volume depletion; hypervolemic hyponatremia presents with edema, , or elevated jugular venous pressure; euvolemic hyponatremia lacks these findings.

Step 3: Urine Studies

Once hypotonicity is confirmed, measure urine osmolality and urine sodium on a spot sample collected before any therapy.

Test	Finding	Interpretation
Urine osmolality	< 100 mOsm/kg	Primary polydipsia, low solute intake, beer potomania
Urine osmolality	> 100 mOsm/kg	Inappropriate ADH activity (SIADH, hypovolemia, hypervolemia)
Urine sodium	< 30 mEq/L	Hypovolemia (extrarenal losses) or hypervolemia (heart failure, cirrhosis)
Urine sodium	> 30 mEq/L	SIADH, renal salt wasting (RSW), diuretic use, hypocortisolism

Caveats: In patients on diuretics, urine sodium may be high regardless of volume status. In SIADH with poor salt intake, urine sodium can be low ^[131]^D5.

Step 4: Additional Diagnostic Tests

When the cause remains unclear, measure serum cortisol (8 AM) and TSH to exclude adrenal insufficiency and hypothyroidism. Plasma copeptin, the surrogate marker of arginine vasopressin, can be measured after hypertonic saline infusion (target Na ≥ 150 mmol/L) to distinguish primary polydipsia from partial central diabetes insipidus with high accuracy (96.5% vs 76.6% for water deprivation test) ^[46]^B2b. This test is not yet routine in all centers but is increasingly used in specialized units.

Fractional excretion of urate (FEurate) helps differentiate SIADH from renal salt wasting. In SIADH, FEurate is elevated during hyponatremia but normalizes after correction; in RSW, it remains persistently elevated ^[1]^D5^[2]^C4. is present in ~70% of SIADH patients ^[131]^D5.

Special Considerations

Thiazide-associated hyponatremia: Suspect when thiazide use is present; risk increases with age and low BMI ^[75]^B2b^[35]^D5. Discontinuation and cation repletion often resolve it.
(TMP/SMX): High-dose therapy can cause hyponatremia mimicking SIADH, but clinical hypovolemia with high renin and aldosterone distinguishes it ^[115]^C4.
Hypocortisolism: Low total CO2, low urea, and low uric acid can mimic SIADH; cortisol measurement is essential ^[131]^D5.
Reset osmostat: A variant of SIADH where ADH secretion is regulated but at a lower osmolality set point; water loading test shows plasma osmolality stabilizes at a lower level.

Imaging

Imaging is directed at underlying causes. Chest CT may reveal causing SIADH ^[153]^C4. Brain MRI is indicated if CNS pathology is suspected (e.g., multiple system atrophy presenting with SIADH ^[149]^C4). Adrenal CT may show bilateral thickening in disseminated causing primary adrenal insufficiency ^[151]^C4.

Biopsy/Histology

Biopsy is not required for the diagnosis of hyponatremia itself. It is obtained to confirm the underlying etiology when indicated (e.g., lung biopsy for suspected SCLC, adrenal biopsy for infectious or malignant adrenal disease).

Pearl: The single most common diagnostic error is misclassifying hypovolemic hyponatremia as euvolemic SIADH, leading to inappropriate fluid restriction; a spot urine sodium < 30 mEq/L with clinical signs of volume depletion should prompt volume repletion rather than water restriction ^[126]^D5^[115]^C4.

Key Diagnostic Tests in Hyponatremia

Test	Finding	Interpretation
Plasma osmolality	< 275 mOsm/kg	Hypotonic hyponatremia
Urine osmolality	< 100 mOsm/kg	Primary polydipsia, low solute intake
Urine osmolality	> 100 mOsm/kg	Inappropriate ADH activity
Urine sodium	< 30 mEq/L	Hypovolemia (extrarenal) or hypervolemia
Urine sodium	> 30 mEq/L	SIADH, RSW, diuretics, hypocortisolism
Fractional excretion of urate	Persistently > 12% after correction	Renal salt wasting ^[1]^D5^[2]^C4
Plasma copeptin (after hypertonic saline)	> 4.9 pmol/L	Central diabetes insipidus excluded ^[46]^B2b
8 AM cortisol	< 3 μg/dL	Adrenal insufficiency

Staging and Risk Stratification

▸Severe hyponatremia (<125 mEq/L) and rapid correction (>8 mEq/L/24h) are the primary risk factors for osmotic demyelination.
▸Low baseline sodium (≤121 mEq/L) and low SUN (≤10 mg/dL) predict a dangerously rapid rise after tolvaptan in SIADH.
▸Mild hyponatremia in ambulatory patients carries a 1.75-fold increased mortality hazard and is an independent risk factor for fracture.

HY High Yield: When ordering tolvaptan for SIADH, check baseline serum sodium and SUN. If both are low (Na ≤121, SUN ≤10), expect a rapid rise and plan for close monitoring or alternative therapy.

Severity classification of hyponatremia follows a three-tier system: mild (130-135 mEq/L), moderate (125-129 mEq/L), and severe (<125 mEq/L). This staging, analogous to KDIGO severity grading, drives the urgency of intervention and the intensity of monitoring. The laboratory threshold for severe hyponatremia (≤120 mEq/L) defines the population at greatest risk for cerebral edema and osmotic demyelination ^[130]^D5.

Risk Stratification for Overcorrection

Rapid correction, defined as a serum sodium increase >8 mEq/L in 24 hours, occurred in 41% of patients presenting with severe hyponatremia (Na <120 mEq/L) in a large retrospective cohort ^[92]^B2b. Independent predictors of overcorrection include younger age, female sex, lower Charlson comorbidity index, lower presenting sodium, and urine sodium <30 mEq/L ^[92]^B2b. Among patients with SIADH treated with , those with both low baseline serum sodium (≤121 mEq/L) and low serum urea nitrogen (SUN ≤10 mg/dL) exhibited a mean 24-hour increase of 15.4 mEq/L, a rate exceeding the safety threshold ^[38]^B3b. Prior hyponatremia, outpatient aldosterone antagonist use, and treatment at an academic center were associated with a lower risk of rapid correction ^[92]^B2b.

(ODS) was documented radiologically in 0.6% of the cohort, but 88% of those with ODS had a preceding sodium increase >8 mEq/L in 24 hours ^[92]^B2b. Risk factors for ODS in chronic hyponatremia, alcoholism, liver disease, malnutrition, malignancy, and hypokalemia, are also independent predictors of a rapid rise ^[116]^C4^[92]^B2b.

Prognostic Stratification and Mortality Risk

Mild hyponatremia (median Na 133 mEq/L) in ambulatory individuals is associated with a 1.75-fold increased hazard of death after adjustment for comorbidities (HR 1.75; 95% CI not calculable from reported data) ^[71]^B2b. In hospitalized patients, the trajectory of serum sodium during admission further refines prognosis: a fluctuating serum sodium trajectory carried the highest in-hospital mortality (OR 4.61; 95% CI, 3.61-5.88) compared with stable normonatremia ^[96]^B2b. Uncorrected and corrected hyponatremia also conferred elevated mortality (OR 1.33 and 1.50, respectively) ^[96]^B2b.

In chronic liver disease, the score, which incorporates serum sodium, outperforms alone for 90-day waitlist mortality, with a c-index of 0.847 (SE 0.007) and a predicted 4.9% reduction in waitlist mortality if used for allocation ^[164]^B2b^[89]^B2b. Each 1-unit decrease in serum sodium (between 125-140 mmol/L) is associated with a 5% increase in the hazard of death (HR 1.05; P<0.001) ^[89]^B2b.

For heart failure, hyponatremia (Na <135 mEq/L) is an independent predictor of mortality (adjusted HR 1.90; 95% CI, 1.10-2.86) ^[161]^B2b. In acute kidney injury, hyponatremia confers a 2-fold odds of AKI (OR 1.97; 95% CI, 1.57-2.47) ^[145]^B2c. Among neonates undergoing cardiac surgery, hyponatremia <130 mmol/L independently predicted AKI (OR 4.1; 95% CI not calculable from reported data) ^[146]^B2b.

Tables

Severity Stage	Serum Sodium (mEq/L)	Clinical Implications
Mild	130-135	Often asymptomatic; increased fracture risk and mortality ^[97]^B2b^[71]^B2b
Moderate	125-129	Neurocognitive deficits may be present; risk of overcorrection moderate
Severe	<125	Symptoms common; high risk of cerebral edema and ODS if overcorrected ^[130]^D5

Risk Factor for Overcorrection	Odds Ratio / Association	Evidence
Low baseline Na (≤121 mEq/L) + low SUN (≤10 mg/dL)	Mean ΔNa 15.4 mEq/L/24h	^[38]^B3b
Urine Na <30 mEq/L	Independent predictor	^[92]^B2b
Younger age, female sex, low comorbidity index	Each associated with rapid correction	^[92]^B2b
Beer potomania, hypokalemia	Present in 63% of ODS cases	^[92]^B2b

Pearl: Baseline serum sodium ≤121 mEq/L combined with SUN ≤10 mg/dL identifies patients at highest risk for overcorrection after tolvaptan, monitor sodium every 4-6 hours and consider desmopressin if the rate exceeds 8 mEq/L in 24 hours ^[38]^B3b^[144]^C4.

Acute Management

▸Severe symptomatic hyponatremia requires immediate treatment with hypertonic saline, with the goal of symptom abatement, not normalization.
▸Overcorrection is associated with increased mortality, particularly in dialysis patients; concurrent dialysate flow may offer a slower correction rate.
▸Low-sodium maintenance fluids can reduce daily sodium burden but do not consistently alter the incidence of dysnatremia.

HY High Yield: In severe symptomatic hyponatremia, initiate hypertonic saline immediately; the goal is to raise sodium by 4-6 mEq/L to stop seizures or coma, not to reach normal range.

! Warning: Avoid overcorrection in chronic hyponatremia: rapid correction increases the risk of osmotic demyelination syndrome and is associated with lower survival (OR 0.33, 95%) [170].

Once the severity classification (outlined in the preceding section) is determined, acute targets the immediate correction of severe symptomatic hyponatremia while rigorously avoiding overcorrection that can lead to (ODS) or increased mortality ^[170]^B2b.

Step 1: Initial Assessment and Severity Classification

Confirm the presence of symptoms (seizures, altered mental status, coma) and the duration of hyponatremia (acute <48 hours vs. chronic). In patients with severe symptoms, regardless of the absolute sodium level, treatment should proceed emergently. In asymptomatic or mildly symptomatic patients, the focus is on identifying the underlying cause and instituting controlled correction.

Step 2: First-Line Intervention for Severe Symptomatic Hyponatremia

Administer intravenous hypertonic saline (3% NaCl) as the first-line therapy ^[18]^D5. The goal is to raise the serum sodium sufficiently to abate symptoms, not to normalize it. In clinical practice, a small bolus is often repeated until symptoms improve. Overcorrection, defined as a rise that exceeds safe limits, must be avoided. In a study of 400 patients undergoing extracorporeal cardiopulmonary resuscitation, those in the overcorrected cluster had significantly lower odds of survival at discharge (OR 0.33) ^[170]^B2b (2b).

Step 3: Second-Line and Adjunctive Management

For patients with symptomatic hyponatremia who are at high risk of ODS (e.g., chronic hyponatremia, alcoholism, malnutrition, hypokalemia), consider administering desmopressin (DDAVP) to prevent overcorrection. This is not a routine first step but a rescue measure when the sodium rises too rapidly. In patients with end-stage kidney disease (ESKD) on hemodialysis, the choice of dialysate flow can modulate the correction rate. A randomized controlled trial of 44 hyponatremic patients (serum sodium <125 mEq/L) showed that concurrent dialysate flow produced a slower, albeit nonsignificant, correction rate compared with countercurrent flow (45.45% vs. 36.36% achieving a safe correction, p=0.44), and no cases of ODS occurred in either group ^[175]^A1b (1b). For patients on peritoneal dialysis, icodextrin (ICO) can cause hyperosmolar hyponatremia in a dose-dependent manner; reducing the dose of ICO may lower the severity of hyponatremia ^[178]^C4 (4).

Step 4: Monitoring and Titration

Check serum sodium every 2 hours during active correction until symptoms resolve, then every 4-6 hours. The maximum safe correction limit in the first 24 hours is generally 6-8 mEq/L for high-risk patients and 10-12 mEq/L for low-risk patients, but these thresholds are derived from observational data and clinical judgment. In the critical care setting, the use of low-sodium maintenance/creep fluids can substantially reduce total daily sodium burden; a meta-analysis of 5 studies (1105 patients) found a mean daily sodium reduction of 117 mmol (95% CI -174 to -59) with low-sodium compared with high-sodium fluids ^[169]^A1a (1a). However, this approach did not significantly alter the incidence of hyper- or hyponatremia in the included studies.

Step 5: Resolution and Transition to Long-Term Management

Once symptoms resolve and the serum sodium is stable, transition to a long-term management strategy targeting the underlying cause (e.g., volume depletion, diuretic use, SIADH). This includes adjusting fluid intake, discontinuing culprits, and considering definitive therapies such as vaptans or salt tablets. The evidence for ongoing management is covered in the subsequent section.

Drug/Modality Comparison Table

Option	Indication / Line	Key Evidence	Outcome	Evidence Level
3% hypertonic saline	Severe symptomatic hyponatremia (first-line)	Review of intravenous solutions ^[18]^D5	Rapid symptom abatement	5 (expert opinion)
Concurrent dialysate flow	Severe hyponatremia in hemodialysis	RCT (n=44) ^[175]^A1b	Slower, nonsignificant correction; no ODS	1b
Low-sodium maintenance fluids	ICU patients (adjunct)	Meta-analysis (5 studies, n=1105) ^[169]^A1a	Mean daily sodium reduction 117 mmol; no change in dysnatremia incidence	1a
Icodextrin dose reduction	Peritoneal dialysis-induced hyponatremia	Case report ^[178]^C4	Normalization of sodium with dose reduction	4

What NOT to Do

Do not correct hyponatremia too rapidly in chronic cases; overcorrection is associated with higher mortality (OR 0.33 for survival in overcorrected cluster) ^[170]^B2b.
Do not use isotonic saline (0.9% NaCl) as first-line therapy for severe symptomatic hyponatremia, as it is less effective at raising sodium quickly ^[18]^D5.
Do not administer hypertonic saline to asymptomatic, hypervolemic patients (e.g., those with heart failure or cirrhosis) without careful consideration of volume status, as it can worsen fluid overload ^[174]^B2b.

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength	Implication for practice
Optimal correction rate in dialysis patients	Concurrent dialysate flow (slower) ^[175]^A1b	Countercurrent flow (standard)	Mild (nonsignificant difference, no ODS in either group)	The choice depends on clinician preference; concurrent flow may be chosen for high-risk patients.
Use of low-sodium maintenance fluids	Reduces daily sodium burden ^[169]^A1a	No proven reduction in dysnatremia incidence	Weak (meta-analysis with high heterogeneity)	May be considered in ICU patients to avoid hypernatremia, but not a primary therapy for hyponatremia.

Pearl: In severe symptomatic hyponatremia, the immediate goal is to raise the serum sodium just enough to abate symptoms, not to normalize it; overcorrection, especially in dialysis patients, is associated with increased mortality (OR 0.33) ^[170]^B2b.

Long-term and Definitive Management

▸Urea is safe, effective, and inexpensive for long-term management of SIADH-induced hyponatremia, with a 47% normalization rate and <3% overcorrection risk.
▸Vaptans (tolvaptan, lixivaptan) are effective second-line agents but carry higher cost and risk of rapid correction; the SHOR score helps identify patients at risk.
▸Empagliflozin is a novel emerging option for chronic SIADH, improving both serum sodium and neurocognitive function in small RCTs.

! Warning: Do not use vaptans in hypovolemic hyponatremia; they worsen volume depletion. Avoid thiazides in SIADH as they are ineffective and cause hypokalemia/AKI.

HY High Yield: The SHOR score (decreased consciousness, vomiting, hypotonic urine, low initial Na, low SUN) predicts overcorrection with tolvaptan; use it to guide dosing and monitoring.

After acute stabilization, the focus shifts to selecting a long-term strategy that prevents recurrence of hyponatremia while avoiding the risks of overcorrection. The choice depends on the underlying cause, volume status, severity, and patient tolerability.

Step 1: Identify Candidates for Chronic Therapy

Not all patients with hyponatremia require indefinite treatment. Correction is indicated when hyponatremia is symptomatic, recurrent, or associated with adverse outcomes such as falls, neurocognitive impairment, or increased mortality ^[37]^D5. The INSIGHT trial showed that tolvaptan improved psychomotor speed in patients with mild to moderate chronic hyponatremia (serum sodium >120-<135 mEq/L) ^[155]^A1b. In hospitalized patients, a targeted correction strategy increased normonatremia rates but did not reduce 30-day mortality or rehospitalization ^[201]^A1b. Thus, the decision to treat must balance potential benefits against the risks and costs of therapy.

Step 2: First-Line Therapy, Fluid Restriction and Urea

For euvolemic hyponatremia, particularly SIADH, fluid restriction (≤1 L/day) is the initial step. However, adherence is poor and many patients fail to respond. A meta-analysis of observational studies found that urea significantly increased serum sodium compared with no treatment (MD 7.99 mEq/L, 95% CI 6.25-9.72) and was comparable to fluid restriction (MD 0.81 mEq/L, 95% CI -0.93 to 2.55) ^[180]^B2a. In a retrospective study of 161 treatment episodes, median urea dose 30 g/day for 4 days raised plasma sodium from 127 to 134 mmol/L, with normalization in 47% ^[206]^B3b. Overcorrection occurred in only 3% and no cases of osmotic demyelination were reported ^[206]^B3b. Urea is inexpensive, well tolerated (poor palatability is the most common side effect), and can be self-administered long-term ^[180]^B2a^[204]^C4.

Step 3: Second-Line Options, Vaptans and SGLT2 Inhibitors

When fluid restriction and urea fail or are not tolerated, vasopressin receptor antagonists (vaptans) are effective. A meta-analysis of 15 RCTs showed vaptans increased the response rate for normalization of serum sodium (RR 3.15) with a weighted mean increase of 5.27 mEq/L ^[181]^A1a. However, vaptans are associated with a higher rate of rapid correction (RR 2.52) and are costly ^[181]^A1a^[118]^D5. Long-term tolvaptan (mean 701 days) maintained serum sodium >135 mmol/L with acceptable safety, but thirst, polyuria, and hypernatremia were noted ^[184]^B2b. The SALT trials confirmed efficacy at day 4 and day 30 ^[185]^A1b.

, an SGLT2 inhibitor, offers a novel approach. In a randomized trial of hospitalized SIADH patients, empagliflozin 25 mg daily plus fluid restriction increased plasma sodium by a median of 10 mmol/L vs 7 mmol/L with placebo (P=0.04) ^[156]^A1b. In chronic SIADH outpatients, empagliflozin 25 mg daily raised serum sodium by 4.1 mmol/L (95% CI 1.7-6.5) and improved MoCA scores by 1.16 points (95% CI 0.05-2.26) ^[183]^A1b. No hypoglycemia or hypotension occurred. Empagliflozin is a promising alternative, but larger studies are needed.

Step 4: Preventing Overcorrection, Risk Stratification and Rescue

Overcorrection (serum sodium rise >12 mmol/L in 24 hours, or >18 mmol/L in 48 hours) must be avoided. The Severe Hyponatremia Overcorrection Risk (SHOR) score predicts this risk: points are assigned for decreased consciousness (2), vomiting (2), severe hypokalemia (1), hypotonic urine (4), volume overload (-5), chest tumor (-5), age >50 (-1 per decade), and initial sodium <110 mmol/L (4) ^[98]^B2b. SHOR score discrimination was c-statistic 0.77 (95% CI 0.73-0.81) ^[98]^B2b.

If overcorrection is imminent or occurring, desmopressin (DDAVP) 1-2 µg IV or SC can halt the rise and even lower sodium by 2-9 mmol/L when combined with 5% dextrose in water ^[205]^C4^[144]^C4. DDAVP is effective in both prevention and reversal ^[205]^C4.

Step 5: Transition and Monitoring

Once normonatremia is achieved, the lowest effective dose of the chosen agent should be maintained. For urea, a typical maintenance dose is 15-30 g/day; for tolvaptan, start 15 mg/day and titrate to 30-60 mg/day based on response ^[184]^B2b. Serum sodium should be checked every 1-2 weeks initially, then monthly. Patients should be educated about symptoms of overcorrection (dysarthria, weakness, ataxia) and advised to seek immediate care if these occur.

Drug/Modality Comparison

Option	Indication/Line	Dose	Key Trial	Outcome	Evidence Level
Urea	First-line (SIADH)	30 g/day (titrate 15-60 g)	Meta-analysis ^[180]^B2a	Increase Na by 7.99 mEq/L vs no treatment	2a
Tolvaptan	Second-line (euvolemic/hypervolemic)	15-60 mg/day	SALT-1/2 ^[185]^A1b	Increased Na at day 4 and day 30	1b
Empagliflozin	Second-line (SIADH)	25 mg/day	Refardt 2020 ^[156]^A1b	+10 mmol/L vs +7 mmol/L (P=0.04)	1b
Lixivaptan	Second-line (euvolemic)	25-100 mg/day	Abraham 2012 ^[179]^A1b	+6.7 mmol/L vs +4.5 mmol/L (P=0.034)	1b

What NOT to Do

Do not use thiazide diuretics or loop diuretics as chronic therapy for SIADH; they are ineffective and increase risk of hypokalemia and acute kidney injury ^[182]^A1b. Do not administer vaptans in patients with hypovolemic hyponatremia. Avoid rapid correction with hypertonic saline in chronic asymptomatic hyponatremia; the risk of osmotic demyelination outweighs benefit ^[116]^C4.

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength	Implication
First-line drug for SIADH	European guidelines (2014) recommend urea, discourage vaptans ^[117]^D5	US practice often uses vaptans as second-line after failed fluid restriction ^[16]^D5	Moderate (differing recommendations)	Urea is cheaper and safer; vaptans are reserved for refractory cases in Europe, but used more widely in the US.
Role of SGLT2 inhibitors	German/European experts suggest empagliflozin as promising but not guideline-endorsed ^[156]^A1b^[183]^A1b	No formal guideline position exists	Mild (emerging evidence)	Consider in patients who cannot tolerate urea or vaptans, but await larger trials.

Pearl: In chronic SIADH, start with fluid restriction and urea (30 g/day); if this fails, add empagliflozin or switch to a vaptan, but always monitor for overcorrection using the SHOR score and have DDAVP available for rescue.

Fluid, Electrolyte & Acid-Base Disorders

▸Hyponatremia rarely occurs in isolation; concurrent electrolyte disorders alter the differential diagnosis and correction strategy.
▸Thiazide diuretics are the classic cause of combined hyponatremia, hypokalemia, and metabolic alkalosis.
▸Acid-base status (bicarbonate) helps differentiate SIAD (normal) from diuretic use (alkalosis) from adrenal insufficiency (acidosis).

HY High Yield: In hyponatremia, a normal potassium and bicarbonate strongly favor SIAD; hypokalemia with metabolic alkalosis points to diuretics or vomiting; hyperkalemia with metabolic acidosis suggests adrenal insufficiency, check cortisol and ACTH.

Long-term of hyponatremia frequently intersects with concurrent electrolyte and acid-base disturbances that modify both the approach and the risk profile. A systematic evaluation of the full electrolyte panel and acid-base status is essential because the pattern of abnormalities often points to the underlying etiology and dictates safe correction strategies.

Potassium and Hyponatremia

Hypokalemia commonly accompanies hyponatremia in thiazide diuretic use, where both cation depletion and impaired urinary dilution contribute ^[35]^D5. The combination of hypokalemia and metabolic alkalosis strongly suggests diuretic excess or vomiting. Conversely, hyperkalemia with hyponatremia raises suspicion for adrenal insufficiency (primary or secondary), which should prompt measurement of cortisol and ACTH ^[128]^C4^[125]^C4. In syndrome of inappropriate antidiuresis (SIAD), serum potassium is typically normal; hypokalemia should trigger a search for an additional cause such as concurrent diuretic therapy or ^[136]^C4. The coexistence of hyponatremia and hypokalemia increases the risk of cardiac arrhythmias and requires simultaneous repletion of both cations.

Calcium, Magnesium, and Phosphate

Hyponatremia is associated with in several settings, including severe illness and certain infections ^[215]^B3b. Hypomagnesemia can cause refractory hypokalemia and may also impair renal concentrating ability, contributing to hyponatremia. In patients receiving or amphotericin B, a triad of hyponatremia, hypomagnesemia, and hypokalemia is characteristic ^[59]^D5. , by contrast, typically impairs urinary concentrating ability and leads to hypernatremia rather than hyponatremia; its presence with hyponatremia should prompt evaluation for ectopic ADH secretion or adrenal insufficiency.

Acid-Base Disturbances

Metabolic alkalosis (elevated bicarbonate) with hyponatremia and hypokalemia is the hallmark of thiazide or loop diuretic use, vomiting, or mineralocorticoid excess. Metabolic acidosis with hyponatremia and hyperkalemia suggests adrenal insufficiency or hyporeninemic (type 4 renal tubular acidosis). A normal bicarbonate and potassium are most consistent with SIAD. The acid-base pattern thus provides a rapid bedside clue to the mechanism of hyponatremia.

Drug-Induced Multielectrolyte Disorders

Several drug classes cause simultaneous electrolyte derangements that complicate hyponatremia management:

Drug Class	Electrolyte Abnormalities	Mechanism
Thiazide diuretics	Hyponatremia, hypokalemia, hypomagnesemia	NaCl cotransporter inhibition, volume depletion, ADH stimulation ^[35]^D5
Immune checkpoint inhibitors	Hyponatremia (SIAD), hypokalemia (RTA), hypercalcemia (PTHrP)	Endocrinopathy, tubulointerstitial nephritis ^[103]^B3b^[203]^D5
Cisplatin	Hyponatremia, hypomagnesemia, hypokalemia	Tubular toxicity, renal salt wasting ^[59]^D5
Amphotericin B	Hyponatremia, hypokalemia, hypomagnesemia, RTA	Tubular membrane injury ^[59]^D5
Antidepressants (SSRIs/SNRIs)	Hyponatremia (SIAD)	Increased ADH secretion; risk higher in elderly ^[218]^A1a
Aldosterone synthase inhibitors	Hyponatremia, hyperkalemia	Reduced aldosterone ^[219]^A1a

Clinical Implications

A comprehensive metabolic panel including sodium, potassium, chloride, bicarbonate, calcium, magnesium, and phosphate should be obtained in every patient with hyponatremia. The pattern of abnormalities guides the differential diagnosis and helps avoid overly rapid correction, which is particularly hazardous when hypokalemia is also present because potassium repletion itself raises serum sodium. Integrated management, addressing all derangements simultaneously, reduces the risk of osmotic demyelination and improves outcomes.

Pearl: In hyponatremia, a normal potassium and bicarbonate strongly favor SIAD; hypokalemia with metabolic alkalosis points to diuretics or vomiting; hyperkalemia with metabolic acidosis suggests adrenal insufficiency, check cortisol and ACTH.

Renal Replacement Therapy, Dialysis Access & Transplantation

▸Hyponatremia in HD and PD patients is independently associated with 1.45- to 1.63-fold higher all-cause mortality, with additive risk from fluid overload.
▸CVVH with low-sodium replacement fluid or concurrent-flow HD minimizes the risk of rapid sodium correction compared to standard HD.
▸Post-transplant hyponatremia is common but not independently associated with mortality; intraoperative use of balanced crystalloids reduces perioperative hyponatremia.

HY High Yield: **High-yield:** In hyponatremic patients starting HD, use a dialysate sodium concentration no more than 2-3 mmol/L above the patient's serum sodium to avoid rapid correction. Concurrent dialysate flow may further slow the rise [175].

! Warning: **Warning:** Standard citrate anticoagulation during CVVHD delivers a substantial sodium load (mean 1754 mmol/day) that can cause excessive correction (>8 mmol/L/24h) in half of patients [230]. Use low-sodium replacement fluid or bag adjustment instead.

Given the high prevalence of hyponatremia in patients with advanced kidney disease, selection of renal replacement therapy (RRT) modality and the design of the dialysis prescription critically influence sodium homeostasis and clinical outcomes. The following sections address modality-specific considerations, dialysate sodium , vascular and peritoneal access, and transplantation as definitive therapy, each with direct implications for hyponatremia risk and correction.

RRT Modality Selection

Hemodialysis (HD) poses the highest risk of rapid sodium correction. In a cohort of 27,180 incident HD patients, both baseline hyponatremia (sodium <138 mEq/L) and time-varying hyponatremia were independently associated with higher all-cause mortality in a U-shaped pattern ^[106]^B3b (3b). A meta-analysis of 13 studies confirmed that hyponatremia in maintenance HD carries a pooled hazard ratio of 1.45 (95% CI 1.31-1.61) for death ^[231]^B2a (2a). The risk is amplified by fluid overload: in a large European registry, hyponatremia combined with fluid overload (>2.5 L) yielded a mortality HR of 1.97 compared with normonatremia and normal fluid status ^[172]^B2b (2b).

Peritoneal dialysis (PD) is associated with hyponatremia through at least two mechanisms. First, icodextrin-based solutions can cause hyperosmolar hyponatremia via absorption of oligosaccharides. A case series and a dose-response report demonstrate that higher daily icodextrin volumes produce more severe hyponatremia, with a nadir of 121 mmol/L at 3 L/day ^[178]^C4^[233]^C4 (4). Second, PD patients with baseline hyponatremia (sodium <135 mEq/L) have a 1.45-fold higher adjusted mortality risk (95% CI 1.29-1.63) compared with those with sodium 140-141 mEq/L, independent of peritonitis risk ^[76]^B2b (2b). Similar associations were reported in a US national PD cohort, where time-dependent sodium <136 mEq/L was associated with incrementally higher death risk ^[105]^B3b (3b).

Continuous venovenous hemofiltration (CVVH) or hemodialysis (CVVHD) is the preferred modality when severe hyponatremia (sodium <120 mEq/L) coexists with acute kidney injury (AKI) requiring dialysis. A teaching case demonstrated successful correction of sodium from <100 mEq/L using CVVH with low-sodium replacement fluid, with single-pool kinetic modeling to control the rate of rise ^[158]^C4 (4). In a retrospective study of 37 critically ill AKI patients with hyponatremia (median sodium 127 mmol/L), CVVHD using standard citrate anticoagulation and commercial dialysate raised sodium by a median of 8 mmol/L (IQR 5-10) in the first 24 hours, but 48.6% of patients exceeded the recommended correction rate (>8 mmol/L/24 h) ^[230]^C4 (4). No cases of central pontine myelinolysis were observed, but the substantial sodium load from trisodium citrate (mean 1754 mmol/day) must be accounted for.

Dialysate Sodium and Correction Rate

Dialysate sodium concentration is the primary lever during HD. In a randomized pilot trial of 44 patients with severe hyponatremia (sodium <125 mEq/L), concurrent dialysate flow (where dialysate and blood flow in the same direction) produced a slower, though nonsignificant, sodium correction rate compared with countercurrent flow, with no cases of osmotic demyelination in either group ^[175]^A1b (1b). The concurrent group also showed a trend toward less neurological deterioration (73.9% vs. 57.1% with no deterioration). While not definitive, this approach may be a safety option when conventional HD is the only available modality.

Cool dialysate (35.0-35.5°C) reduces intradialytic hypotension (RR 0.67) and increases mean arterial pressure, but comes at the cost of thermal discomfort (RR 1.55) ^[168]^A1a (1a). This is relevant because hypotension during HD can trigger rapid fluid shifts and exacerbate cerebral edema in hyponatremic patients, though the meta-analysis did not specifically examine hyponatremic subgroups.

Pediatric CKRT requires careful sodium management. A computational simulation of pediatric CKRT (5-80 kg) found that bag adjustment and continuous infusion of sodium are universally feasible, whereas post-filter bag change frequently fails in patients ≤20 kg at higher sodium targets due to inability to maintain minimum post-filter flow ^[235]^D5 (5). An open-access tool (https://crrt-sodium.netlify.app) is available for individualizing the correction plan.

Transplantation

Definitive therapy for end-stage kidney disease, kidney transplantation restores intrinsic renal function but introduces unique hyponatremia risks. At 3 months post-transplant, 1258 recipients underwent a water-loading test: most failed to maintain plasma sodium (slope -0.6±0.4 mmol/L per hour vs. -0.12±0.3 in controls; p<0.001). Each 1 mmol/L per hour steeper sodium decline was independently associated with a composite outcome of death or graft loss (HR 1.73, 95% CI 1.23-2.45) and lower measured GFR at 12 months ^[40]^B2b (2b).

Intraoperative fluid choice affects perioperative sodium. In a retrospective study of 282 living-donor kidney transplant recipients, balanced crystalloid (Plasma-Lyte) resulted in less hyponatremia and metabolic acidosis during surgery compared with half-saline, and recipients had higher eGFR at 1 month and 1 year after adjustment ^[229]^B3b (3b). The PLUTO randomized trial in children found that Plasma-Lyte-148 did not reduce acute hyponatremia (53% vs. 58%;, 0.34-1.75) but significantly lowered hyperchloremia, acidosis, and hypomagnesemia ^[65]^A1b (1b).

Post-transplant hyponatremia may also arise from calcineurin inhibitor nephrotoxicity. A case of severe symptomatic hyponatremia was attributed to despite normal trough levels ^[124]^C4 (4). Additionally, transplantation of a kidney from a donor with transmitted the tubulopathy phenotype, causing hyponatremia in the recipient ^[224]^C4 (4). Despite these risks, in a prospective cohort of 1315 recipients, hyponatremia (sodium <136 mmol/L) at 6 months post-transplant was not associated with mortality (HR 1.02, p=0.97) or graft loss ^[234]^B2b (2b).

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength of disagreement	Implication for practice
Optimal dialysate sodium for hyponatremic HD patients	Concurrent dialysate flow may reduce correction rate ^[175]^A1b (1b)	Countercurrent flow is standard; no high-quality evidence favoring concurrent flow	Mild (single pilot trial; no guidelines)	Concurrent flow can be considered in severe hyponatremia, but data are insufficient to recommend routinely
Use of icodextrin in PD patients with hyponatremia	Icodextrin is effective for ultrafiltration; dose reduction may mitigate hyponatremia ^[178]^C4 (4)	Icodextrin causes hyperosmolar hyponatremia; on-label use can still produce this complication ^[233]^C4 (4)	Moderate (case series vs. case report; no guideline)	Monitor serum sodium closely when initiating icodextrin; consider dose reduction or switch to dextrose if hyponatremia develops
Correction rate during RRT for severe hyponatremia	CVVH with low-sodium replacement fluid allows slow, controlled correction ^[158]^C4 (4)	Standard CVVHD with citrate anticoagulation often exceeds 8 mmol/L/24h ^[230]^C4 (4)	Moderate (observational; no direct comparison)	Use low-sodium replacement fluid or bag adjustment; monitor sodium every 2-4 hours; avoid citrate-based anticoagulation if rapid correction is a concern

Pearl: In patients with hyponatremia requiring dialysis, avoid HD with standard countercurrent dialysate if possible; consider CVVH with low-sodium replacement fluid or concurrent-flow HD to prevent rapid correction, and monitor sodium every 2-4 hours to keep the rise <8 mmol/L per 24 hours.

RRT Modalities and Hyponatremia Risk

Modality	Key Hyponatremia Risk	Correction Rate Control	Mortality Evidence
Hemodialysis (HD)	Rapid sodium rise; fluid overload amplifies risk	Poor without specialized dialysate; concurrent flow may slow rise	HR 1.45 (95% CI 1.31-1.61) ^[231]^B2a (2a)
Peritoneal dialysis (PD)	Icodextrin-induced hyperosmolar hyponatremia; volume depletion	Inherently slower; daily exchange pattern	AHR 1.45 (95% CI 1.29-1.63) ^[76]^B2b (2b)
CVVH/CVVHD	Sodium load from citrate anticoagulation	Good with low-sodium replacement fluid; bag adjustment feasible	HR 1.97 with fluid overload ^[172]^B2b (2b)
Kidney transplantation	Impaired osmoregulation; calcineurin inhibitor effect	Variable; water-loading test predicts risk	Not associated with mortality (HR 1.02, p=0.97) ^[234]^B2b (2b)

History and Evolution of Treatment

▸SALT-1 and SALT-2 established tolvaptan as effective for euvolemic/hypervolemic hyponatremia, with sustained correction confirmed in the SALTWATER extension.
▸The EFFUSE-FLUID trial showed that adding furosemide and oral NaCl to fluid restriction offers no additional sodium correction and increases acute kidney injury and hypokalemia.
▸Empagliflozin is a promising emerging therapy for SIADH, with early trials showing a 4.1 mmol/L rise in sodium and improved neurocognitive function.
▸A 2026 randomized trial of targeted hyponatremia correction found no reduction in 30-day mortality or rehospitalization despite achieving higher normonatremia rates.

HY High Yield: The EFFUSE-FLUID trial is the only randomized study to directly test the common practice of adding furosemide and salt to fluid restriction in SIADH; it found no benefit and increased harm.

! Warning: Despite the appeal of vaptans, their use carries a boxed warning for liver injury and requires strict monitoring of serum sodium to avoid overcorrection. The 2026 targeted correction trial [201] reminds us that achieving normonatremia does not automatically improve survival.

The therapeutic approach to hyponatremia has evolved from empirical fluid restriction to targeted pharmacological intervention, shaped by pivotal trials and sobering safety lessons. Understanding this timeline grounds current practice in its evidentiary origins.

Early Treatment: Fluid Restriction and the Thiazide Era

Before the 1970s, treatment relied on water restriction and addressing the underlying cause. The recognition that thiazide diuretics precipitate hyponatremia, particularly in the elderly, came from seminal studies showing that hydrochlorothiazide 100 mg/day impaired free water clearance more in older than younger volunteers ^[236]^B2b. The first pharmacological alternatives were lithium and demeclocycline. In 1978, a landmark trial of 10 patients with SIADH found that demeclocycline 600-1200 mg/day restored serum sodium to 139 ± 1.1 mmol/L within 5-14 days, whereas lithium 900 mg/day was ineffective and caused central-nervous-system toxicity ^[244]^C4. Demeclocycline became the drug of choice for chronic SIADH, despite its nephrotoxicity and photosensitivity.

The Hypertonic Saline Controversy and the ODS Shadow

Hypertonic saline has been used for nearly a century, but its safety was challenged in the 1980s when studies linked rapid correction of severe chronic hyponatremia to the (ODS) ^[122]^D5. This led to consensus guidelines limiting correction to ≤ 8 mmol/L per day in high-risk patients ^[77]^D5. Recent large retrospective studies have questioned this limit, suggesting ODS is rare and that slow correction may increase mortality. However, a 2023 review by 20 experts from nine countries concluded that current safeguards should not be abandoned, citing referral bias and confounding in the challenger studies ^[129]^D5. The controversy persists, but the precautionary principle still dominates clinical practice.

The Vaptan Revolution: SALT Trials and Beyond

Vasopressin V2-receptor antagonists, vaptans, represented a breakthrough by directly promoting aquaresis. The SALT-1 and SALT-2 trials (2006) randomized 448 patients with euvolemic or hypervolemic hyponatremia to oral tolvaptan 15 mg (titrated to 60 mg) or placebo. Serum sodium increased significantly more with tolvaptan at both day 4 and day 30 (P < 0.001); hyponatremia recurred after discontinuation ^[185]^A1b. The SALTWATER extension (mean follow‑up 701 days) showed sustained correction with an acceptable safety margin; hypernatremia >145 mmol/L led to discontinuation in only one patient ^[184]^B2b. Lixivaptan 50 mg/day (titrated to 25-100 mg) in hospitalized patients with euvolemic hyponatremia raised sodium by 6.7 mmol/L vs 4.5 mmol/L with placebo at day 7 (P = 0.034) ^[179]^A1b. Satavaptan achieved response rates of 79-83% in SIADH, with maintained efficacy over 12 months ^[186]^A1b. The INSIGHT trial (2016) suggested that tolvaptan-induced correction of chronic hyponatremia (mean sodium increase from 129 to 136 mmol/L) improved psychomotor speed (treatment effect 0.27, 95%; P = 0.03) ^[155]^A1b.

Revisiting Non-Pharmacologic Options: The EFFUSE-FLUID Trial

Despite the vaptan era, fluid restriction remained first-line for SIADH. The EFFUSE-FLUID randomized trial (2020) tested whether adding 20-40 mg/day and/or oral NaCl 3 g/day to fluid restriction improved correction in 92 patients with SIADH and sodium ≤130 mmol/L. The change in sodium at day 4 was 5 mmol/L in all groups (P = 0.7), and there was no difference in time to reach sodium ≥130 mmol/L. Acute kidney injury and hypokalemia (K ≤ 3.0 mmol/L) were more common with furosemide ^[182]^A1b. This trial confirmed that fluid restriction alone is as effective as these combination strategies, while avoiding the added harm.

Emerging Therapies: SGLT2 Inhibitors and Urea

SGLT2 inhibitors offer a novel mechanism, osmotic diuresis via urinary glucose excretion. A 2020 randomized trial of 87 hospitalized SIADH patients (sodium <130 mmol/L) found that 25 mg/day added to fluid restriction <1000 mL/24 h increased median sodium by 10 vs 7 mmol/L over 4 days (P = 0.04) ^[156]^A1b. A subsequent crossover trial in 14 outpatients with chronic SIADH showed a sustained rise of 4.1 mmol/L (95% CI 1.7-6.5; P = 0.004) and improved MoCA score by 1.16 points (95% CI 0.05-2.26) ^[183]^A1b. Oral urea, long used in selected centers, was evaluated retrospectively in 161 treatment episodes: a median dose of 30 g/day increased sodium from 127 to 134 mmol/L, with overcorrection in only 3% and no ODS ^[206]^B3b.

The Targeted Correction Strategy: A Negative Trial

A 2026 multicenter trial randomized 2173 hospitalized hyponatremic patients (sodium <130 mmol/L) to a multifaceted targeted correction intervention or routine care. The intervention achieved normonatremia in 60.4% vs 46.2% (P < 0.001) but did not reduce the composite outcome of 30-day death or rehospitalization (20.5% vs 21.8%; absolute difference -1.3 percentage points, 95% CI -4.9 to 2.2; P = 0.45) ^[201]^A1b. This trial underscores that correcting the serum sodium level alone may not improve clinical outcomes if the underlying disease remains unaddressed.

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength	Implication
Rate of correction for chronic hyponatremia	Limit to ≤ 8 mmol/L/day (ESICM/ESEM/ESICM/ESICM guidelines)	Faster correction permitted if ODS risk low (some recent retrospective studies)	Guidelines cite multiple cohort studies; challengers cite referral bias ^[77]^D5^[129]^D5	Precaution remains standard; ODS is devastating but rare
Role of vaptans as first-line therapy	First-line for euvolemic/hypervolemic hyponatremia (US label)	Reserve for cases failing fluid restriction (European guidelines)	Moderate; vaptans carry risk of overcorrection and liver toxicity	Clinician must weigh risk/benefit for each patient

Pearl: The history of hyponatremia treatment is a cautionary tale: each new therapy, from demeclocycline to vaptans to SGLT2 inhibitors, was initially hailed as a breakthrough, but only the vaptan trials (SALT-1/2) have provided robust efficacy data, while the EFFUSE-FLUID trial proved that adding furosemide and salt to fluid restriction adds harm without benefit. No therapy has yet demonstrated a mortality reduction in a randomized trial ^[201]^A1b.

Landmark Trials in Hyponatremia Treatment

Trial	Year	Population	Intervention	Key Result
SALT-1/2 ^[185]^A1b	2006	Euvolemic/hypervolemic hyponatremia	Tolvaptan 15-60 mg/day vs placebo	Increased serum Na at day 4 and day 30 (P<0.001)
SALTWATER ^[184]^B2b	2010	Chronic hyponatremia (extension)	Tolvaptan (open-label)	Sustained correction over 701 days; hypernatremia rare
Lixivaptan ^[179]^A1b	2012	Euvolemic hyponatremia (hospitalized)	Lixivaptan 50 mg/day (titrated) vs placebo	Na increase 6.7 vs 4.5 mmol/L at day 7 (P=0.034)
INSIGHT ^[155]^A1b	2016	Mild-moderate chronic hyponatremia	Tolvaptan vs placebo	Improved psychomotor speed (P=0.03); no effect on composite neurocognition
EFFUSE-FLUID ^[182]^A1b	2020	SIADH (Na ≤130 mmol/L)	FR alone vs FR+furosemide vs FR+furosemide+NaCl	No difference in Na correction; AKI/hypokalemia more with furosemide
Empagliflozin (acute) ^[156]^A1b	2020	SIADH (hospitalized, Na <130)	Empagliflozin 25 mg/day + FR vs placebo+FR	Na increase 10 vs 7 mmol/L at day 4 (P=0.04)
Empagliflozin (chronic) ^[183]^A1b	2022	Chronic SIADH (outpatients)	Empagliflozin 25 mg/day vs placebo	Na increase 4.1 mmol/L (P=0.004); MoCA +1.16 points
Targeted correction ^[201]^A1b	2026	Hospitalized hyponatremia (Na <130)	Multifaceted correction vs routine care	30-day death/rehospitalization 20.5% vs 21.8% (P=0.45)

Complications (Chronic Systemic Sequelae)

▸Osmotic demyelination syndrome occurs in 0.5-0.6% of severe hyponatremia cases, nearly always after 24-hour correction >8 mEq/L; re-lowering sodium with desmopressin and hypotonic fluids is the key rescue maneuver.
▸In CKD and dialysis patients, hyponatremia synergizes with fluid overload to amplify mortality risk (HR 1.97); correction of hyponatremia should be considered as part of volume management.

! Warning: Rapid correction of chronic hyponatremia (≥12 mEq/L in 24 h) is the strongest modifiable risk factor for osmotic demyelination syndrome. If overcorrection occurs, re-lower the serum sodium with desmopressin 2-4 mcg IV and 5% dextrose in water at 3 mL/kg/h to prevent irreversible neurologic injury [26, 92].

The expanding therapeutic options for hyponatremia, from urea and vaptans to SGLT2 inhibitors, have improved outcomes, yet the disorder itself and its carry well-defined complications that clinicians must anticipate. Chronic hyponatremia, even when mild, is not benign; it independently increases mortality, fracture risk, and neurocognitive deficits.

(ODS)

ODS is the most feared complication of rapid sodium correction. In a large retrospective cohort of patients with serum sodium <120 mEq/L, radiologic ODS occurred in only 0.6% of cases, but nearly all patients with ODS (88%) had a documented 24-hour correction >8 mEq/L ^[92]^B2b. Risk factors include alcoholism, liver disease, hypokalemia, malnutrition, and severe hyponatremia (sodium <120 mEq/L) ^[92]^B2b^[112]^D5. When overcorrection is recognized early, re-lowering serum sodium using desmopressin and hypotonic fluids reduces mortality in animal models ^[26]^D5 and is recommended in clinical practice. The tetracycline antibiotic minocycline (200 mg orally twice daily for 5 days) has been shown in animal models to prevent ODS by inhibiting microglial activation and blood-brain barrier breakdown ^[23]^D5^[87]^D5^[199]^D5; human data remain limited. Urea, compared with vaptans or hypertonic saline, may cause less brain demyelination when correction is rapid, likely because its osmotic effect is distributed across total body water ^[195]^D5.

Neuropsychiatric and Gait Impairments

Chronic hyponatremia (sodium 125-135 mEq/L) degrades cognitive function: in the INSIGHT trial, tolvaptan correction improved psychomotor speed (treatment effect 0.27, 95%) ^[155]^A1b. Rat models demonstrate deficits in gait, fear-conditioning memory, and hippocampal long-term potentiation, all reversible after correction ^[41]^D5. These deficits translate clinically to increased falls and fractures. In a cohort of women, hyponatremia <135 mEq/L was independently associated with fracture (after adjustment for bone density) ^[97]^B2b. Among elderly patients with chronic hyponatremia >90 days, the adjusted hazard ratio for was 4.52 (95% CI 2.14-9.6) ^[102]^B3b.

Mortality and Cardiovascular Outcomes

Mild hyponatremia (median 133 mEq/L) in ambulatory individuals carries a hazard ratio for death of 1.75 (95% CI 1.2-2.5) after adjusting for comorbidities ^[71]^B2b. In CKD stages 3-4, hyponatremia is associated with all-cause mortality (HR 1.16 for cardiovascular death, 1.48 for malignancy-related death) ^[104]^B3b. Among incident dialysis patients, pre-ESKD hyponatremia <130 mEq/L increases post-transition mortality by 54% (HR 1.54, 95% CI 1.34-1.76) ^[217]^B3b. In hemodialysis patients, the combination of hyponatremia and fluid overload amplifies risk: mortality HR 1.97 versus normal sodium and euvolemia ^[172]^B2b.

Bone Health

Hyponatremia directly stimulates osteoclast activity to mobilize sodium from bone, decreasing bone mineral density and increasing fragility. Even mild chronic hyponatremia (sodium 130-135 mEq/L) doubles the risk of low-trauma fracture ^[55]^D5^[97]^B2b.

Complication	Frequency	Prevention	Management
Osmotic demyelination syndrome	0.5%-0.6% of severe hyponatremia ^[92]^B2b	Limit 24-h correction to ≤8 mEq/L; avoid rapid correction in high-risk patients	Re-lower sodium with DDAVP + hypotonic fluids; consider minocycline (200 mg BID × 5 d) ^[23]^D5^[87]^D5
Excess mortality (ambulatory)	HR 1.75 ^[71]^B2b	Treat underlying cause; consider therapy for chronic hyponatremia	Optimize volume status, use urea or vaptans if indicated
Excess mortality in CKD/dialysis	HR 1.54-1.97 ^[217]^B3b^[172]^B2b	Monitor fluid status; avoid large Na swings	Manage fluid overload aggressively in hyponatremic dialysis patients

Controversies and Guideline Disagreement

Whether rapid correction is ever beneficial remains debated. A 2026 meta-analysis reported that overcorrection was associated with increased neurologic complications (OR 4.23, 95% CI 2.93-6.11) but lower mortality (OR 0.67, 95% CI 0.47-0.97), though the evidence was very low certainty ^[251]^B2a. A large retrospective study found faster correction associated with fewer 90-day deaths or delayed neurologic events (RD -9.0 percentage points for fast vs. slow correction) ^[254]^B2b. These studies are limited by confounding, and current guidelines continue to recommend slow, controlled correction, particularly in patients at high risk for ODS ^[77]^D5.

Pearl: In any patient with hyponatremia, the single most actionable complication to prevent is osmotic demyelination, limit 24-hour correction to ≤8 mEq/L in high-risk patients, and if overcorrection occurs, re-lower sodium with desmopressin and hypotonic fluids within 12-24 hours to reduce neurologic harm ^[26]^D5^[92]^B2b.

Prognosis and Natural History

▸Even mild hyponatremia (130-134 mEq/L) is independently associated with increased short- and long-term mortality across hospitalized, CKD, dialysis, and older populations.
▸Serum sodium trajectory, fluctuating or overcorrected patterns, carries higher mortality risk than the admission sodium value.
▸Chronic uncorrected hyponatremia perpetuates systemic complications; correction must be controlled to avoid osmotic demyelination.

HY High Yield: A fluctuating serum sodium trajectory (in-hospital variation ≥6 mEq/L) carries the highest mortality risk (OR 4.61 for in-hospital death), monitoring trends is more prognostic than a single value [96].

The chronic systemic sequelae of hyponatremia, gait instability, osteoporosis, cognitive impairment, translate into quantifiable mortality risk across diverse populations. Serum sodium concentration functions as an independent prognostic marker, with risk increasing proportionally to the depth and duration of the disorder.

Mortality Across Populations

In hospitalized patients, even mild hyponatremia (130-134 mEq/L) carries excess risk. A cohort of over 60,000 adults found that serum sodium variations of ≥6 mEq/L, regardless of admission sodium, increased hospital and 1-year mortality in a dose-dependent manner (adjusted OR 1.47 to 5.48) ^[57]^B2b. Among multimorbid older adults (mean age 79, median 11 comorbidities), hyponatremia at admission conferred a higher 1-year mortality (HR 1.41), with a linear trend across severity categories (HR 1.31 for mild to 2.64 for severe) ^[258]^B2b.

In chronic kidney disease, hyponatremia prior to end-stage renal disease transition is associated with a 54% higher all-cause mortality after dialysis initiation (HR 1.54) ^[217]^B3b. Among 72,163 hemodialysis patients, hyponatremia (Na <135 mmol/L) combined with fluid overload increased mortality risk nearly twofold (HR 1.97) ^[172]^B2b. The risk pattern is approximately linear over the first four patient-months of cumulative exposure and then plateaus ^[90]^B2b.

In liver disease, each 1 mEq/L decrease in serum sodium (between 125 and 140 mmol/L) raises waiting-list mortality by 5% (HR 1.05, P<0.001) ^[89]^B2b. For geriatric patients, moderate-to-severe hyponatremia (<130 mEq/L) increases 30-day mortality nearly fourfold (HR 3.75) ^[216]^B3b.

Sodium Trajectories and Correction Risk

Beyond the absolute value, the trajectory of serum sodium during hospitalization independently predicts outcomes. A study of 43,539 hospitalized patients identified five sodium trajectories; the fluctuating pattern carried the highest risk of in-hospital mortality (OR 4.61, 95% CI 3.61-5.88) and 1-year mortality (HR 2.10, 95% CI 1.89-2.33) ^[96]^B2b. Overcorrection of hyponatremia, defined as a rise exceeding guideline limits, is associated with decreased survival. In out-of-hospital cardiac arrest patients receiving extracorporeal resuscitation, the overcorrected cluster had significantly lower odds of survival to discharge (OR 0.33) ^[170]^B2b.

Natural History if Untreated

Chronic, uncorrected hyponatremia (Na persistently <135 mEq/L) perpetuates the allostatic adaptations described in the prior section: bone demineralization, gait instability, and cognitive decline, each independently linked to fractures and falls. The risk of (ODS) is a function of correction velocity, not of the hyponatremia itself; rapid correction in predisposed individuals (alcoholism, liver disease, malnutrition) can trigger ODS even without preceding hyponatremia ^[116]^C4. In DDAVP-associated hyponatremia, withholding the drug led to a mean sodium rise of 37.1 mEq/L in 48 hours and resulted in death (23%) or severe brain damage (69%) ^[80]^C4.

Pearl: The nadir serum sodium and its trajectory of correction are stronger predictors of outcome than the absolute value alone; a fluctuating course carries the highest mortality risk and demands vigilant monitoring.

Selected Mortality Risk of Hyponatremia by Population

Population	Comparison	Adjusted Risk (95% CI)	Reference
Multimorbid older adults	Hyponatremia vs normonatremia	1-year mortality HR 1.41 (1.11-1.78)	^[258]^B2b
Pre-ESKD CKD	Na <130 vs 135-144 mEq/L	All-cause mortality HR 1.54 (1.34-1.76)	^[217]^B3b
Hemodialysis patients	Na <135 + fluid overload	Mortality HR 1.97 (1.82-2.12)	^[172]^B2b
Hospitalized patients	Na fluctuation ≥6 mEq/L	In-hospital mortality OR 1.47-5.48	^[57]^B2b
Geriatric hip fracture	Na <130 vs ≥130 mEq/L	30-day mortality HR 3.75 (1.74-8.08)	^[216]^B3b

Special Populations

▸In elderly patients, thiazide and SSRI initiation requires baseline and follow-up sodium monitoring due to a 5-fold increased hyponatremia risk.
▸In pregnancy, vaptans are contraindicated; fluid restriction and hypertonic saline are mainstays.
▸In immunocompromised patients on targeted cancer therapies, routine sodium surveillance is essential as hyponatremia is a common grade ≥3 adverse event.

! Warning: In DDAVP-associated hyponatremia, withholding DDAVP can trigger rapid overcorrection and brain injury; continue DDAVP while administering hypertonic saline [80].

HY High Yield: SSRI initiation in patients ≥60 years carries a 29% higher hyponatremia risk compared with other antidepressants (HR 1.29) [210].

Prognosis in hyponatremia is not uniform; age, renal function, and immune status profoundly alter risk and treatment.

Pediatrics

Perioperative fluid in children: Plasma-Lyte-148 did not reduce acute hyponatremia versus standard fluids (53% vs 58%; OR 0.77) but lowered hyperchloremia and acidosis ^[65]^A1b. Balanced crystalloids are preferred for large-volume resuscitation, particularly after kidney transplantation ^[225]^D5. Hyponatremia predicts recurrence despite benzodiazepine prophylaxis (OR 0.713 per mEq/L decrease) ^[107]^B3b. In -associated hyponatremia (e.g., therapy), continuing DDAVP while correcting with hypertonic saline prevents rapid overcorrection and brain injury ^[80]^C4. Nephrogenic SIAD due to AVPR2 activating mutations presents in male infants but also affects heterozygous females ^[200]^C4.

Pregnancy

Pregnancy lowers the osmotic threshold for vasopressin release, reducing baseline serum sodium by 4-5 mEq/L ^[139]^C4. are contraindicated due to teratogenicity risk. Fluid restriction is first-line; for severe symptomatic hyponatremia follows standard protocols. Activating AVPR2 mutations can worsen during pregnancy and may be transmitted to the fetus ^[139]^C4. Delivery planning should involve maternal-fetal medicine; postpartum sodium typically normalizes.

Elderly

Age-related decline in renal diluting capacity and polypharmacy drive hyponatremia risk. diuretics increase risk 5-fold (HR 4.95), with age and low BMI as effect modifiers ^[75]^B2b. Second-generation antidepressants, especially s, increase 30-day hospitalization risk for hyponatremia 5-fold (RR 5.46); absolute risk is 1.31% ^[67]^B2b. In patients aged ≥60 years, SSRI initiation carries a 29% higher risk versus other antidepressants (HR 1.29) ^[210]^B3b. Chronic mild hyponatremia (126-140 mEq/L) is independently associated with cognitive impairment (OR 1.30, 95% CI 1.06-1.61) and cognitive decline (OR 1.37, 95% CI 1.06-1.77) in community-dwelling older men ^[93]^B2b, and increases risk through gait instability and possibly increased bone resorption ^[55]^D5. High ambient temperatures disproportionately affect those >80 years, with severe hyponatremia rates exceeding 100 episodes per million person-days at temperatures >22°C ^[86]^B2b. Clinical action: check serum sodium before and 2-4 weeks after starting thiazides or SSRIs in patients >65 years; correct mild hyponatremia to reduce fall and fracture risk.

Immunocompromised

Kidney transplant recipients have impaired osmoregulation: 3 months post-transplant, a steeper plasma sodium decline during water loading independently predicts allograft loss (HR 2.04 per 1 mmol/L/h decrease; 95% CI 1.19-3.51) ^[40]^B2b. can cause severe symptomatic hyponatremia even at normal trough levels ^[124]^C4. Transplantation of a kidney can transfer the tubulopathy phenotype, leading to unexpected hyponatremia ^[224]^C4. Among cancer patients on targeted therapies, hyponatremia is a common grade ≥3 adverse event: (6-8%) ^[188]^B2b^[189]^B2b, vismodegib ^[190]^B2b, and toripalimab (3.1%) ^[202]^A1b. for Pneumocystis pneumonia in non-HIV patients: pretreatment hyponatremia independently increases risk of grade ≥3 adverse events ^[209]^B3b. Management: monitor serum sodium before each cycle of these agents; correct per standard guidelines but avoid overly rapid correction given chronic hyponatremia.

Pearl: In elderly patients initiating thiazides or SSRIs, check serum sodium at baseline and within 2-4 weeks, the 5-fold increased risk is modifiable with early detection.

Prevention, Screening & Surveillance

▸Primary prevention targets modifiable triggers: water intoxication, NSAIDs, porphyrinogenic drugs, and severe exercise dehydration.
▸Secondary prevention with midodrine reduces incident hyponatremia by 36% in pediatric cirrhosis (NNT 2.8) [264].
▸Routine electrolyte surveillance is recommended for cancer patients on ICIs, children with pneumonia, AHP patients, and dialysis patients, with specific screening intervals.

HY High Yield: In dialysis patients, the combination of fluid overload (>2.5 L above normal) and hyponatremia (<135 mmol/L) carries a mortality HR of 1.97, surveillance of both parameters is mandatory [172].

Building on the pregnancy-specific considerations, prevention of hyponatremia requires a systematic approach across at-risk populations, anchored to guideline-graded recommendations and defined intervals.

Primary Prevention

Avoiding precipitating factors is the cornerstone. In endurance athletes, individualized hydration plans and electrolyte replacement prevent exertional hyponatremia, while NSAIDs should be avoided due to risk of acute kidney injury ^[34]^D5. Water intoxication, which can cause acute severe hyponatremia (serum sodium as low as 111 mEq/L) with intravascular , is prevented by patient education on safe fluid intake ^[267]^C4. In patients with acute hepatic porphyria (AHP), discontinuation of porphyrinogenic drugs and chemicals is critical ^[263]^A1c.

Secondary Prevention (Preventing Recurrence)

In cirrhotic children with awaiting , adding midodrine to standard medical therapy reduced new-onset hyponatremia from 56% to 20% (NNT = 2.8) ^[264]^A1b. For dialysis patients, surveillance of fluid status is especially important in those with hyponatremia, as the combination of fluid overload and hyponatremia carries a 1.97-fold increased mortality risk (HR 1.97) ^[172]^B2b. In cancer patients receiving immune checkpoint inhibitors (ICIs), routine electrolyte surveillance is warranted because any-grade hyponatremia occurs in 5.0% (95% CI 2.3%-11.9%) and grade ≥3 in 5.5% (95% CI 3.1%-9.6%) ^[83]^B2a. In AHP, recurrent acute attacks (≥4/year) warrant prophylactic therapy with intravenous hemin or subcutaneous givosiran ^[263]^A1c.

Screening Recommendations

Screening should target populations with high prevalence or risk:

Population	Screening Method	Recommendation & Interval	Source
Hospitalized cancer patients	Serum sodium on admission	Screen all; hyponatremia (OR 1.97 for AKI) ^[145]^B2c	^[145]^B2c
Children with severe pneumonia	Serum electrolytes	Monitor electrolytes; 39% have hyponatremia ^[269]^B2b	^[269]^B2b
Patients with AHP (especially women 15-50 yr with abdominal pain)	Random urine porphobilinogen and δ-aminolevulinic acid, plus serum sodium	Screen at presentation; 42/77 (55%) have hyponatremia ^[266]^C4	^[263]^A1c, ^[266]^C4
Neonates with risk factors (vomiting, weight loss)	Serum sodium	Monitor if symptomatic; seizures can occur at Na 105.9 mmol/L ^[268]^C4	^[268]^C4
Dialysis patients	Monthly plasma sodium and bioimpedance spectroscopy	Monitor for hyponatremia; fluid overload increases mortality risk ^[172]^B2b	^[172]^B2b

For patients with reninoma, paraneoplastic SIADH may cause hyponatremia; serum sodium should be checked in those with and hypokalemia ^[270]^C4.

Patient Education

Patients should be counseled to recognize early symptoms of hyponatremia (nausea, headache, confusion, balance loss) ^[83]^B2a and to avoid excessive water intake, especially during or after exercise ^[34]^D5. In AHP, patients must avoid porphyrinogenic drugs and maintain adequate carbohydrate intake ^[263]^A1c.

Pearl: In patients with hyponatremia, simultaneous fluid overload amplifies mortality risk more than hyponatremia alone (HR 1.97 vs 1.26), surveillance of volume status is as important as sodium level ^[172]^B2b.

References

[1]
Maesaka JK, Imbriano LJ, Ali NM et al.. “Is it cerebral or renal salt wasting?” Kidney international (2009). PMID: 19641485 ↗
L5REVIEW_NARRATIVECited in: Definition, Classification and Nomenclature, Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders
[2]
Bitew S, Imbriano L, Miyawaki N et al.. “More on renal salt wasting without cerebral disease: response to saline infusion.” Clinical journal of the American Society of Nephrology : CJASN (2009). PMID: 19201917 ↗
L4CASE_REPORTCited in: Definition, Classification and Nomenclature, Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Complications (Chronic Systemic Sequelae)
[3]
Woodfine JD, van Walraven C. “Criteria for Hyponatremic Overcorrection: Systematic Review and Cohort Study of Emergently Ill Patients.” Journal of general internal medicine (2019). PMID: 31452039 ↗
L2SR_OBSCited in: Definition, Classification and Nomenclature
[4]
Park S, Cho H, Park S et al.. “Simple Postoperative AKI Risk (SPARK) Classification before Noncardiac Surgery: A Prediction Index Development Study with External Validation.” Journal of the American Society of Nephrology : JASN (2018). PMID: 30563915 ↗
L2OTHERCited in: Definition, Classification and Nomenclature, Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Special Populations & Pregnancy
[5]
Hartley IR, Ginsberg JS, Diamantidis CJ et al.. “Consideration of ICD-9 code-derived disease-specific safety indicators in CKD.” Clinical journal of the American Society of Nephrology : CJASN (2013). PMID: 24052221 ↗
L2OTHERCited in: Definition, Classification and Nomenclature, Pathophysiology and Mechanism, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Complications (Chronic Systemic Sequelae), Prognosis and Natural History
[6]
Gillespie CS, Mihaela-Vasilica A, Dhaliwal J et al.. “Hyponatremia Incidence After Subarachnoid Hemorrhage and Association with Outcomes: Systematic Review and Meta-Analysis.” World neurosurgery (2025). PMID: 39732459 ↗
L1SR_OBSCited in: Definition, Classification and Nomenclature
[7]
Nosadini M, Toldo I, Tascini B et al.. “LGI1 and CASPR2 autoimmunity in children: Systematic literature review and report of a young girl with Morvan syndrome.” Journal of neuroimmunology (2019). PMID: 31352183 ↗
L4SR_OBSCited in: Definition, Classification and Nomenclature
[8]
van Griensven J, Bah EI, Haba N et al.. “Electrolyte and Metabolic Disturbances in Ebola Patients during a Clinical Trial, Guinea, 2015.” Emerging infectious diseases (2016). PMID: 27869610 ↗
L2TRIAL_NONRANDOMCited in: Definition, Classification and Nomenclature
[9]
Watkins PB, Lewis JH, Kaplowitz N et al.. “Clinical Pattern of Tolvaptan-Associated Liver Injury in Subjects with Autosomal Dominant Polycystic Kidney Disease: Analysis of Clinical Trials Database.” Drug safety (2015). PMID: 26188764 ↗
L2TRIAL_NONRANDOMCited in: Definition, Classification and Nomenclature
[10]
Ramanathan S, Kumar P, Mishra K et al.. “Isotonic versus Hypotonic Parenteral Maintenance Fluids in Very Severe Pneumonia.” Indian journal of pediatrics (2015). PMID: 26027555 ↗
L1RCTCited in: Definition, Classification and Nomenclature
[11]
Suppadungsuk S, Krisanapan P, Kazeminia S et al.. “Hyponatremia Correction and Osmotic Demyelination Syndrome Risk: A Systematic Review and Meta-Analysis.” Kidney medicine (2024). PMID: 39967825 ↗
L1SR_OBSCited in: Definition, Classification and Nomenclature
[12]
Adhikari P, Rana R, Punja R et al.. “Prevalence and impact of hyponatremia in chronic obstructive pulmonary disease. A systematic review and meta-analysis.” The Libyan journal of medicine (2026). PMID: 41846300 ↗
L1SR_OBSCited in: Definition, Classification and Nomenclature, Epidemiology, Etiology and Risk Factors, Long-term and Definitive Management
[13]
Arieff AI, Gabbai R, Goldfine ID. “Cerebral Salt-Wasting Syndrome: Diagnosis by Urine Sodium Excretion.” The American journal of the medical sciences (2017). PMID: 29078838 ↗
L3TRIAL_NONRANDOMCited in: Definition, Classification and Nomenclature
[14]
Bovée DM, Visser WJ, Middel I et al.. “A Randomized Trial of Distal Diuretics versus Dietary Sodium Restriction for Hypertension in Chronic Kidney Disease.” Journal of the American Society of Nephrology : JASN (2020). PMID: 31996411 ↗
L1RCTCited in: Pathophysiology and Mechanism, Clinical Presentation, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Long-term and Definitive Management, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae), Prognosis and Natural History, Special Populations & Pregnancy
[15]
Kubota K, Sakaguchi Y, Hamano T et al.. “Prognostic value of hypochloremia versus hyponatremia among patients with chronic kidney disease-a retrospective cohort study.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2020). PMID: 30346587 ↗
L2COHORTCited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Long-term and Definitive Management, Complications (Chronic Systemic Sequelae), Prognosis and Natural History, Special Populations & Pregnancy
[16]
Lehrich RW, Ortiz-Melo DI, Patel MB et al.. “Role of vaptans in the management of hyponatremia.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2013). PMID: 23725974 ↗
L5CASE_REPORTCited in: Pathophysiology and Mechanism, Clinical Presentation, Diagnosis and Workup, Long-term and Definitive Management, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae)
[17]
Portales-Castillo I, Sterns RH, Bress J et al.. “Where Do the Salt and Water Go? A Case of Profound Hyponatremia.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2018). PMID: 30266221 ↗
L4CASE_REPORTCited in: Pathophysiology and Mechanism, Staging and Risk Stratification (KDIGO), Complications (Chronic Systemic Sequelae)
[18]
Severs D, Rookmaaker MB, Hoorn EJ. “Intravenous solutions in the care of patients with volume depletion and electrolyte abnormalities.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2015). PMID: 25921718 ↗
L5CASE_REPORTCited in: Pathophysiology and Mechanism, Acute Management
[19]
Esposito P, Rampino T, Gregorini M et al.. “Severe symptomatic hyponatremia during sibutramine therapy: a case report.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2008). PMID: 18487000 ↗
L4CASE_REPORTCited in: Pathophysiology and Mechanism, Staging and Risk Stratification (KDIGO)
[20]
Ishii T, Ohtake T, Yasu T et al.. “A rare case of combined syndrome of inappropriate antidiuretic hormone secretion and Fanconi syndrome in an elderly woman.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2006). PMID: 16797399 ↗
L4CASE_REPORTCited in: Pathophysiology and Mechanism
[21]
Workeneh BT, Jhaveri KD, Rondon-Berrios H. “Hyponatremia in the cancer patient.” Kidney international (2020). PMID: 32497528 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Prognosis and Natural History
[22]
Greenberg A, Verbalis JG. “Vasopressin receptor antagonists.” Kidney international (2006). PMID: 16672911 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[23]
Takagi H, Sugimura Y, Suzuki H et al.. “Minocycline prevents osmotic demyelination associated with aquaresis.” Kidney international (2014). PMID: 24759153 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[24]
Banki E, Fisi V, Moser S et al.. “Specific disruption of calcineurin-signaling in the distal convoluted tubule impacts the transcriptome and proteome, and causes hypomagnesemia and metabolic acidosis.” Kidney international (2021). PMID: 34252449 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders
[25]
Fenton RA, Poulsen SB, de la Mora Chavez S et al.. “Renal tubular NHE3 is required in the maintenance of water and sodium chloride homeostasis.” Kidney international (2017). PMID: 28385297 ↗
L5OTHERCited in: Pathophysiology and Mechanism
[26]
Gankam Kengne F, Soupart A, Pochet R et al.. “Re-induction of hyponatremia after rapid overcorrection of hyponatremia reduces mortality in rats.” Kidney international (2009). PMID: 19606078 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Complications (Chronic Systemic Sequelae)
[27]
Lee JW, Alsady M, Chou CL et al.. “Single-tubule RNA-Seq uncovers signaling mechanisms that defend against hyponatremia in SIADH.” Kidney international (2017). PMID: 28843412 ↗
L5OTHERCited in: Pathophysiology and Mechanism
[28]
Cil O, Esteva-Font C, Tas ST et al.. “Salt-sparing diuretic action of a water-soluble urea analog inhibitor of urea transporters UT-A and UT-B in rats.” Kidney international (2015). PMID: 25993324 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Long-term and Definitive Management, Complications (Chronic Systemic Sequelae)
[29]
Alam U, Rath S, Javed J et al.. “Efficacy and safety of lorundrostat in uncontrolled hypertension: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials.” Naunyn-Schmiedeberg's archives of pharmacology (2025). PMID: 41379320 ↗
L1SR_MA_RCTCited in: Pathophysiology and Mechanism, Long-term and Definitive Management
[30]
Mubeen M, Rai KD, Sangtiani AK et al.. “Efficacy and Safety of Lorundrostat in Uncontrolled and/or Treatment Resistant Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.” High blood pressure & cardiovascular prevention : the official journal of the Italian Society of Hypertension (2025). PMID: 41107674 ↗
L1SR_MA_RCTCited in: Pathophysiology and Mechanism, Long-term and Definitive Management
[31]
Berl T. “An elderly patient with chronic hyponatremia.” Clinical journal of the American Society of Nephrology : CJASN (2012). PMID: 23037983 ↗
L4CASE_REPORTCited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders, Special Populations & Pregnancy
[32]
Palmer BF, Perazella MA, Choi MJ. “American Society of Nephrology Quiz and Questionnaire 2013: electrolyte and acid-base.” Clinical journal of the American Society of Nephrology : CJASN (2014). PMID: 24558051 ↗
L5CASE_REPORTCited in: Pathophysiology and Mechanism, Diagnosis and Workup, Long-term and Definitive Management, Complications (Chronic Systemic Sequelae)
[33]
Orman ES, Fortune BE, John BV et al.. “AGA Clinical Practice Update on the Management of Ascites, Volume Overload, and Hyponatremia in Cirrhosis: Expert Review.” Gastroenterology (2025). PMID: 41114681 ↗
L1GUIDELINECited in: Pathophysiology and Mechanism
[34]
Becerra LA, Mansour SG. “Exercise and Kidney Health: Core Curriculum 2026.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2025). PMID: 41389078 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders, Prevention, Screening & Surveillance
[35]
Filippone EJ, Ruzieh M, Foy A. “Thiazide-Associated Hyponatremia: Clinical Manifestations and Pathophysiology.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2019). PMID: 31606239 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Clinical Presentation, Diagnosis and Workup, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[36]
Combs S, Berl T. “Dysnatremias in patients with kidney disease.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2013). PMID: 24239050 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders
[37]
Portales-Castillo I, Sterns RH. “Allostasis and the Clinical Manifestations of Mild to Moderate Chronic Hyponatremia: No Good Adaptation Goes Unpunished.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2018). PMID: 30554800 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Long-term and Definitive Management, Complications (Chronic Systemic Sequelae), Prognosis and Natural History
[38]
Morris JH, Bohm NM, Nemecek BD et al.. “Rapidity of Correction of Hyponatremia Due to Syndrome of Inappropriate Secretion of Antidiuretic Hormone Following Tolvaptan.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2018). PMID: 29478867 ↗
L3OTHERCited in: Pathophysiology and Mechanism, Staging and Risk Stratification (KDIGO), Long-term and Definitive Management, History and Evolution of Treatment
[39]
Cannatà A, Anastasia G, De Marzo V et al.. “Diuretic strategies in acute heart failure: a systematic review and network meta-analysis of randomized clinical trials.” European heart journal. Cardiovascular pharmacotherapy (2026). PMID: 40929381 ↗
L1SR_OBSCited in: Pathophysiology and Mechanism
[40]
Mazloum M, Jouffroy J, Brazier F et al.. “Osmoregulation Performance and Kidney Transplant Outcome.” Journal of the American Society of Nephrology : JASN (2019). PMID: 31217325 ↗
L2OTHERCited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders, Renal Replacement Therapy, Dialysis Access & Transplantation, Prognosis and Natural History, Special Populations & Pregnancy
[41]
Fujisawa H, Sugimura Y, Takagi H et al.. “Chronic Hyponatremia Causes Neurologic and Psychologic Impairments.” Journal of the American Society of Nephrology : JASN (2015). PMID: 26376860 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Clinical Presentation, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[42]
de Groot T, Sinke AP, Kortenoeven ML et al.. “Acetazolamide Attenuates Lithium-Induced Nephrogenic Diabetes Insipidus.” Journal of the American Society of Nephrology : JASN (2015). PMID: 26574046 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders
[43]
Wang J, Li X, Ke Y et al.. “GPR48 increases mineralocorticoid receptor gene expression.” Journal of the American Society of Nephrology : JASN (2011). PMID: 22135314 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders
[44]
Sterns RH, Silver SM. “Cerebral salt wasting versus SIADH: what difference?” Journal of the American Society of Nephrology : JASN (2008). PMID: 18216309 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Clinical Presentation, Diagnosis and Workup
[45]
Gankam Kengne F, Nicaise C, Soupart A et al.. “Astrocytes are an early target in osmotic demyelination syndrome.” Journal of the American Society of Nephrology : JASN (2011). PMID: 21885671 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Long-term and Definitive Management
[46]
Fenske W, Refardt J, Chifu I et al.. “A Copeptin-Based Approach in the Diagnosis of Diabetes Insipidus.” The New England journal of medicine (2018). PMID: 30067922 ↗
L2OTHERCited in: Pathophysiology and Mechanism, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae)
[47]
Saxena M, Laffin L, Borghi C et al.. “Lorundrostat in Participants With Uncontrolled Hypertension and Treatment-Resistant Hypertension: The Launch-HTN Randomized Clinical Trial.” JAMA (2025). PMID: 40587141 ↗
L1RCTCited in: Pathophysiology and Mechanism
[48]
Danziger J, Zeidel ML. “Osmotic homeostasis.” Clinical journal of the American Society of Nephrology : CJASN (2014). PMID: 25078421 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders, Prognosis and Natural History
[49]
Rosner MH, Kirven J. “Exercise-associated hyponatremia.” Clinical journal of the American Society of Nephrology : CJASN (2006). PMID: 17699400 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders
[50]
Pendergraft WF, Herlitz LC, Thornley-Brown D et al.. “Nephrotoxic effects of common and emerging drugs of abuse.” Clinical journal of the American Society of Nephrology : CJASN (2014). PMID: 25035273 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[51]
Campbell GA, Rosner MH. “The agony of ecstasy: MDMA (3,4-methylenedioxymethamphetamine) and the kidney.” Clinical journal of the American Society of Nephrology : CJASN (2008). PMID: 18684895 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders
[52]
Abouelmagd AA, Ramadan S, Sayed MS et al.. “Efficacy and safety of lorundrostat in uncontrolled hypertension: a meta-analysis.” Naunyn-Schmiedeberg's archives of pharmacology (2025). PMID: 41251750 ↗
L1SR_OBSCited in: Pathophysiology and Mechanism, Long-term and Definitive Management
[53]
Shubietah A, Elgendy MS, Emara A et al.. “Low-Dose Triple-Pill of Telmisartan, Amlodipine, and Indapamide for Initial Hypertension Treatment: A GRADE-Assessed Meta-analysis of Randomized Trials.” High blood pressure & cardiovascular prevention : the official journal of the Italian Society of Hypertension (2025). PMID: 41222871 ↗
L1SR_OBSCited in: Pathophysiology and Mechanism, Long-term and Definitive Management
[54]
Karam S, Rosner MH, Sprangers B et al.. “Cancer therapy in patients with reduced kidney function.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2024). PMID: 38914465 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Diagnosis and Workup, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Prognosis and Natural History
[55]
Ayus JC, Negri AL, Kalantar-Zadeh K et al.. “Is chronic hyponatremia a novel risk factor for hip fracture in the elderly?” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2012). PMID: 23114899 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Clinical Presentation, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[56]
Rossi GP, Calò LA, Maiolino G et al.. “Ultrafiltration for the treatment of congestion: a window into the lung for a better caress to the heart.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2013). PMID: 24009283 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders, Renal Replacement Therapy, Dialysis Access & Transplantation, Complications (Chronic Systemic Sequelae)
[57]
Thongprayoon C, Cheungpasitporn W, Yap JQ et al.. “Increased mortality risk associated with serum sodium variations and borderline hypo- and hypernatremia in hospitalized adults.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2020). PMID: 31219584 ↗
L2OTHERCited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors, Diagnosis and Workup, Prognosis and Natural History
[58]
de Bragança AC, Moyses ZP, Magaldi AJ. “Carbamazepine can induce kidney water absorption by increasing aquaporin 2 expression.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2010). PMID: 20525972 ↗
L5OTHERCited in: Pathophysiology and Mechanism, Epidemiology, Etiology and Risk Factors
[59]
Zietse R, Zoutendijk R, Hoorn EJ. “Fluid, electrolyte and acid-base disorders associated with antibiotic therapy.” Nature reviews. Nephrology (2009). PMID: 19322184 ↗
L5REVIEW_NARRATIVECited in: Pathophysiology and Mechanism, Fluid, Electrolyte & Acid-Base Disorders
[60]
Lamarche F, Ammann H, Dallaire G et al.. “The risk of sodium overcorrections in severe hyponatremia and the utility of desmopressin: a large retrospective study.” Clinical kidney journal (2024). PMID: 40235629 ↗
L4COHORTCited in: Pathophysiology and Mechanism
[61]
Vogt K, Widmer D, Kirsch M et al.. “Validation of new diagnostic indices to simplify hyponatremia therapy assessment in patients on thiazide diuretics: study protocol of a randomized, controlled, parallel-group trial (THAT-Study).” Trials (2025). PMID: 40646556 ↗
L5TRIAL_NONRANDOMCited in: Pathophysiology and Mechanism
[62]
Ibarra F, Garcia M, Deshpande S et al.. “Bicarbonate Administration in Severe Hyponatremia (BASH): A Retrospective Cohort Study of 8.4% Sodium Bicarbonate in Patients with Preserved and Reduced Renal Clearance.” The Journal of emergency medicine (2026). PMID: 42190319 ↗
L2COHORTCited in: Pathophysiology and Mechanism, Clinical Presentation, Diagnosis and Workup, Long-term and Definitive Management, Prognosis and Natural History, Special Populations & Pregnancy
[63]
Del Castillo Tirado FJ, Briongos Figuero LS, García-Rubio S et al.. “The role of point-of-care ultrasound in the evaluation and management of hyponatremia: a systematic review.” Internal and emergency medicine (2026). PMID: 41528666 ↗
L2SR_OBSCited in: Pathophysiology and Mechanism, Diagnosis and Workup
[64]
Shalabi L, Tawfik AM, Al Zoubi BM et al.. “Efficacy and safety of lorundrostat in patients with uncontrolled or resistant hypertension: A systematic review and meta-analysis with trial sequential analysis.” Vascular pharmacology (2025). PMID: 41067555 ↗
L1SR_OBSCited in: Pathophysiology and Mechanism, Staging and Risk Stratification (KDIGO)
[65]
Hayes WN, Laing E, Brown R et al.. “A pragmatic, open-label, randomized controlled trial of Plasma-Lyte-148 versus standard intravenous fluids in children receiving kidney transplants (PLUTO).” Kidney international (2023). PMID: 37914088 ↗
L1RCTCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Renal Replacement Therapy, Dialysis Access & Transplantation, History and Evolution of Treatment, Special Populations & Pregnancy
[66]
Abraham WT, Decaux G, Josiassen RC et al.. “Oral lixivaptan effectively increases serum sodium concentrations in outpatients with euvolemic hyponatremia.” Kidney international (2012). PMID: 22932122 ↗
L1RCTCited in: Epidemiology, Etiology and Risk Factors, Long-term and Definitive Management, History and Evolution of Treatment, Special Populations & Pregnancy
[67]
Gandhi S, Shariff SZ, Al-Jaishi A et al.. “Second-Generation Antidepressants and Hyponatremia Risk: A Population-Based Cohort Study of Older Adults.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2016). PMID: 27773479 ↗
L2COHORTCited in: Epidemiology, Etiology and Risk Factors, Staging and Risk Stratification (KDIGO), Special Populations & Pregnancy
[68]
Nigwekar SU, Wenger J, Thadhani R et al.. “Hyponatremia, mineral metabolism, and mortality in incident maintenance hemodialysis patients: a cohort study.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2013). PMID: 23591291 ↗
L2COHORTCited in: Epidemiology, Etiology and Risk Factors, Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation, Special Populations & Pregnancy
[69]
Paz-Ares L, Borghaei H, Liu SV et al.. “Efficacy and safety of first-line maintenance therapy with lurbinectedin plus atezolizumab in extensive-stage small-cell lung cancer (IMforte): a randomised, multicentre, open-label, phase 3 trial.” Lancet (London, England) (2025). PMID: 40473449 ↗
L1RCTCited in: Epidemiology, Etiology and Risk Factors, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Prognosis and Natural History, Special Populations & Pregnancy
[70]
Ayus JC, Armstrong D, Arieff AI. “Hyponatremia with hypoxia: effects on brain adaptation, perfusion, and histology in rodents.” Kidney international (2006). PMID: 16614721 ↗
L5OTHERCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Complications (Chronic Systemic Sequelae)
[71]
Gankam-Kengne F, Ayers C, Khera A et al.. “Mild hyponatremia is associated with an increased risk of death in an ambulatory setting.” Kidney international (2013). PMID: 23325088 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), History and Evolution of Treatment, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[72]
Kokko JP. “Symptomatic hyponatremia with hypoxia is a medical emergency.” Kidney international (2006). PMID: 16614718 ↗
L5OTHERCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Complications (Chronic Systemic Sequelae)
[73]
Liamis G, Milionis H, Elisaf M. “A review of drug-induced hyponatremia.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2008). PMID: 18468754 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders
[74]
Hoorn EJ, Zietse R. “Hyponatremia and mortality: moving beyond associations.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2013). PMID: 23291150 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders
[75]
Rodenburg EM, Hoorn EJ, Ruiter R et al.. “Thiazide-associated hyponatremia: a population-based study.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2013). PMID: 23602191 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Special Populations & Pregnancy
[76]
Teitelbaum I, Zhao J, Tu C et al.. “Associations Between Serum Sodium, Peritoneal Dialysis-Associated Peritonitis, and Mortality in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS).” American journal of kidney diseases : the official journal of the National Kidney Foundation (2025). PMID: 40220849 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation, Prognosis and Natural History, Special Populations & Pregnancy
[77]
Sterns RH, Rondon-Berrios H. “Revisiting New Data on the Mortality Benefit of Rapid Correction of Hyponatremia: Déjà Vu All Over Again.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2025). PMID: 41093163 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae)
[78]
Doshi SM, Shah P, Lei X et al.. “Hyponatremia in hospitalized cancer patients and its impact on clinical outcomes.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2011). PMID: 22001181 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors
[79]
Kupferman J, Amador JJ, Lynch KE et al.. “Characterization of Mesoamerican Nephropathy in a Kidney Failure Hotspot in Nicaragua.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2016). PMID: 27575010 ↗
L4OTHERCited in: Epidemiology, Etiology and Risk Factors, Complications (Chronic Systemic Sequelae)
[80]
Achinger SG, Arieff AI, Kalantar-Zadeh K et al.. “Desmopressin acetate (DDAVP)-associated hyponatremia and brain damage: a case series.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2014). PMID: 25107337 ↗
L4CASE_REPORTCited in: Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Prognosis and Natural History, Special Populations & Pregnancy
[81]
Tear AA, Fauziah N, Riswari SF et al.. “Prognostic factors in malaria patients with acute kidney injury: a systematic review and meta analysis.” Renal failure (2026). PMID: 42185742 ↗
L2SR_OBSCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Complications (Chronic Systemic Sequelae)
[82]
Li H, Qiao D, Hu K. “Factors associated with hyponatremia in patients with acute spinal cord injury: a systematic review and meta-analysis.” Frontiers in medicine (2026). PMID: 42164164 ↗
L2SR_OBSCited in: Epidemiology, Etiology and Risk Factors
[83]
Vitale E, Maistrello L, Ciccimarra F et al.. “Hyponatremia in cancer patients receiving immune checkpoint inhibitors: the ARON-MOUSEION-014 meta-analysis.” Cancer metastasis reviews (2026). PMID: 41844878 ↗
L2SR_OBSCited in: Epidemiology, Etiology and Risk Factors, Long-term and Definitive Management, Complications (Chronic Systemic Sequelae), Prevention, Screening & Surveillance
[84]
Rosner MH, Rondon-Berrios H, Sterns RH. “Syndrome of Inappropriate Antidiuresis.” Journal of the American Society of Nephrology : JASN (2024). PMID: 39621420 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders
[85]
Adrogué HJ, Madias NE. “The challenge of hyponatremia.” Journal of the American Society of Nephrology : JASN (2012). PMID: 22626822 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders
[86]
Issa I, Skov J, Falhammar H et al.. “The Association of Outdoor Temperature with Severe Hyponatremia.” Journal of the American Society of Nephrology : JASN (2024). PMID: 40029748 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders, Special Populations & Pregnancy
[87]
Gankam-Kengne F, Soupart A, Pochet R et al.. “Minocycline protects against neurologic complications of rapid correction of hyponatremia.” Journal of the American Society of Nephrology : JASN (2010). PMID: 21051736 ↗
L5OTHERCited in: Epidemiology, Etiology and Risk Factors, Long-term and Definitive Management, Complications (Chronic Systemic Sequelae)
[88]
Uyeki TM, Mehta AK, Davey RT et al.. “Clinical Management of Ebola Virus Disease in the United States and Europe.” The New England journal of medicine (2016). PMID: 26886522 ↗
L4OTHERCited in: Epidemiology, Etiology and Risk Factors, Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[89]
Kim WR, Biggins SW, Kremers WK et al.. “Hyponatremia and mortality among patients on the liver-transplant waiting list.” The New England journal of medicine (2008). PMID: 18768945 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders, Prognosis and Natural History, Special Populations & Pregnancy
[90]
Pinter J, Canaud B, Mayne KJ et al.. “Associations of Abnormal Fluid Status, Plasma Sodium Disorders, and Low Dialysate Sodium with Mortality in Patients on Hemodialysis.” Clinical journal of the American Society of Nephrology : CJASN (2024). PMID: 39514693 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Acute Management, Fluid, Electrolyte & Acid-Base Disorders, Renal Replacement Therapy, Dialysis Access & Transplantation, Prognosis and Natural History, Special Populations & Pregnancy
[91]
Rondon-Berrios H, Berl T. “Mild Chronic Hyponatremia in the Ambulatory Setting: Significance and Management.” Clinical journal of the American Society of Nephrology : CJASN (2015). PMID: 26109207 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[92]
George JC, Zafar W, Bucaloiu ID et al.. “Risk Factors and Outcomes of Rapid Correction of Severe Hyponatremia.” Clinical journal of the American Society of Nephrology : CJASN (2018). PMID: 29871886 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Staging and Risk Stratification (KDIGO), Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[93]
Nowak KL, Yaffe K, Orwoll ES et al.. “Serum Sodium and Cognition in Older Community-Dwelling Men.” Clinical journal of the American Society of Nephrology : CJASN (2018). PMID: 29439092 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Special Populations & Pregnancy
[94]
Chawla A, Sterns RH, Nigwekar SU et al.. “Mortality and serum sodium: do patients die from or with hyponatremia?” Clinical journal of the American Society of Nephrology : CJASN (2011). PMID: 21441132 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Special Populations & Pregnancy
[95]
Xu R, Pi HC, Xiong ZY et al.. “Hyponatremia and Cognitive Impairment in Patients Treated with Peritoneal Dialysis.” Clinical journal of the American Society of Nephrology : CJASN (2015). PMID: 26231192 ↗
L4OTHERCited in: Epidemiology, Etiology and Risk Factors, Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation, Special Populations & Pregnancy
[96]
Chewcharat A, Thongprayoon C, Cheungpasitporn W et al.. “Trajectories of Serum Sodium on In-Hospital and 1-Year Survival among Hospitalized Patients.” Clinical journal of the American Society of Nephrology : CJASN (2020). PMID: 32213501 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Prognosis and Natural History, Special Populations & Pregnancy
[97]
Kinsella S, Moran S, Sullivan MO et al.. “Hyponatremia independent of osteoporosis is associated with fracture occurrence.” Clinical journal of the American Society of Nephrology : CJASN (2010). PMID: 20056759 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), History and Evolution of Treatment, Complications (Chronic Systemic Sequelae)
[98]
Woodfine JD, Sood MM, MacMillan TE et al.. “Derivation and Validation of a Novel Risk Score to Predict Overcorrection of Severe Hyponatremia: The Severe Hyponatremia Overcorrection Risk (SHOR) Score.” Clinical journal of the American Society of Nephrology : CJASN (2019). PMID: 31189541 ↗
L2OTHERCited in: Epidemiology, Etiology and Risk Factors, Long-term and Definitive Management
[99]
Knechtle B, Scheer V, Nikolaidis PT et al.. “The Comrades Marathon: a narrative review of physiological responses and health implications in the world's oldest ultra-marathon.” Frontiers in physiology (2026). PMID: 42232809 ↗
L5SR_OBSCited in: Epidemiology, Etiology and Risk Factors
[100]
Hu W, Qin J, Qiang L et al.. “Risk factors for hepatic encephalopathy in patients following transjugular intrahepatic portosystemic shunt: a meta-analysis and systematic review.” BMC surgery (2026). PMID: 41965603 ↗
L3SR_OBSCited in: Epidemiology, Etiology and Risk Factors, History and Evolution of Treatment
[101]
Saavedra D, Estupiñan-Bohórquez A, Figueroa F et al.. “Impact of liver cirrhosis on the clinical profile and outcomes in community-acquired pneumonia: A systematic review.” Chronic illness (2026). PMID: 41944478 ↗
L2SR_OBSCited in: Epidemiology, Etiology and Risk Factors, Complications (Chronic Systemic Sequelae)
[102]
Ayus JC, Fuentes NA, Negri AL et al.. “Mild prolonged chronic hyponatremia and risk of hip fracture in the elderly.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2016). PMID: 27190372 ↗
L3OTHERCited in: Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[103]
Seethapathy H, Rusibamayila N, Chute DF et al.. “Hyponatremia and other electrolyte abnormalities in patients receiving immune checkpoint inhibitors.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2021). PMID: 33374011 ↗
L3OTHERCited in: Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders
[104]
Huang H, Jolly SE, Airy M et al.. “Associations of dysnatremias with mortality in chronic kidney disease.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2017). PMID: 27220754 ↗
L3OTHERCited in: Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[105]
Ravel VA, Streja E, Mehrotra R et al.. “Serum sodium and mortality in a national peritoneal dialysis cohort.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2017). PMID: 27358272 ↗
L3OTHERCited in: Epidemiology, Etiology and Risk Factors, Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation, Special Populations & Pregnancy
[106]
Rhee CM, Ravel VA, Ayus JC et al.. “Pre-dialysis serum sodium and mortality in a national incident hemodialysis cohort.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2015). PMID: 26410882 ↗
L3OTHERCited in: Epidemiology, Etiology and Risk Factors, Staging and Risk Stratification (KDIGO), Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation
[107]
Ahmadi S, Mosayebi N, Akbari A et al.. “Recurrence of febrile convulsions in children treated with intermittent benzodiazepines: a retrospective study investigating predisposing factors.” BMC pediatrics (2026). PMID: 42062853 ↗
L3COHORTCited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Long-term and Definitive Management, History and Evolution of Treatment, Special Populations & Pregnancy
[108]
Li L, Gao J, Wang H et al.. “Dual receptor therapy with pituitrin for spinal cord injury-induced diabetes insipidus: A propensity-matched retrospective cohort study.” Chinese journal of traumatology = Zhonghua chuang shang za zhi (2026). PMID: 41832062 ↗
L3COHORTCited in: Epidemiology, Etiology and Risk Factors, History and Evolution of Treatment
[109]
Zornoza-González E, Saz-Lara A, Cavero-Redondo I et al.. “Association between hyponatremia and mortality in neurocritical patients with traumatic brain injury: A systematic review and meta-analysis.” European journal of internal medicine (2026). PMID: 42203531 ↗
L1SR_OBSCited in: Epidemiology, Etiology and Risk Factors
[110]
Arroyo V, Fernández J. “Management of hepatorenal syndrome in patients with cirrhosis.” Nature reviews. Nephrology (2011). PMID: 21826080 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders
[111]
Jovanovich A, Berl T. “Mortality and serum sodium in CKD--yet another U‑shaped curve.” Nature reviews. Nephrology (2012). PMID: 22473511 ↗
L5OTHERCited in: Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders, Prognosis and Natural History
[112]
Crismale JF, Meliambro KA, DeMaria S et al.. “Prevention of the Osmotic Demyelination Syndrome After Liver Transplantation: A Multidisciplinary Perspective.” American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons (2017). PMID: 28422408 ↗
L5REVIEW_NARRATIVECited in: Epidemiology, Etiology and Risk Factors, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[113]
Ghodsi M, Beigi EH, Eftekhari M et al.. “Effect of normal saline and half saline preservation serums on sodium levels, blood pressure, and acidosis in PICU patients.” Medicine (2026). PMID: 41894282 ↗
L1RCTCited in: Epidemiology, Etiology and Risk Factors, Long-term and Definitive Management, History and Evolution of Treatment
[114]
Garde A, Patel S, Molitor L et al.. “Perioperative hyponatremia in total joint arthroplasty: A systematic review of prevalence, risk factors, outcomes, and management.” Journal of orthopaedics (2026). PMID: 42179367 ↗
L2SR_OBSCited in: Epidemiology, Etiology and Risk Factors
[115]
Babayev R, Terner S, Chandra S et al.. “Trimethoprim-associated hyponatremia.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2013). PMID: 23891358 ↗
L4CASE_REPORTCited in: Clinical Presentation, Diagnosis and Workup, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment
[116]
Shah MK, Mandayam S, Adrogué HJ. “Osmotic Demyelination Unrelated to Hyponatremia.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2017). PMID: 29277507 ↗
L4CASE_REPORTCited in: Clinical Presentation, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Prognosis and Natural History
[117]
Sterns RH, Silver SM, Hix JK. “Urea for hyponatremia?” Kidney international (2015). PMID: 25635717 ↗
L5OTHERCited in: Clinical Presentation, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders
[118]
Jovanovich AJ, Berl T. “Where vaptans do and do not fit in the treatment of hyponatremia.” Kidney international (2012). PMID: 23254896 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Diagnosis and Workup, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders
[119]
Hall AM, Vilasi A, Garcia-Perez I et al.. “The urinary proteome and metabonome differ from normal in adults with mitochondrial disease.” Kidney international (2014). PMID: 25207879 ↗
L3OTHERCited in: Clinical Presentation, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[120]
Seay NW, Lehrich RW, Greenberg A. “Diagnosis and Management of Disorders of Body Tonicity-Hyponatremia and Hypernatremia: Core Curriculum 2020.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2019). PMID: 31606238 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders
[121]
Baker M, Perazella MA. “NSAIDs in CKD: Are They Safe?” American journal of kidney diseases : the official journal of the National Kidney Foundation (2020). PMID: 32479922 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[122]
Rondon-Berrios H, Sterns RH. “Hypertonic Saline for Hyponatremia: Meeting Goals and Avoiding Harm.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2021). PMID: 34508830 ↗
L5OTHERCited in: Clinical Presentation, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment
[123]
Suárez V, Picotin R, Fassbender R et al.. “Chronic Hyponatremia and Brain Structure and Function Before and After Treatment.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2024). PMID: 38184092 ↗
L2OTHERCited in: Clinical Presentation, Diagnosis and Workup, Special Populations & Pregnancy
[124]
Bagchi S, Husain Zaidi S, Prasad Mathur R. “Severe symptomatic hyponatremia--an uncommon presentation of tacrolimus nephrotoxicity.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2011). PMID: 21454354 ↗
L4CASE_REPORTCited in: Clinical Presentation, Long-term and Definitive Management, Renal Replacement Therapy, Dialysis Access & Transplantation, Special Populations & Pregnancy
[125]
Li SG, Long T, Yu R et al.. “Adrenal involvement in antiphospholipid syndrome and SLE-spectrum disease: a systematic review and pooled individual-patient analysis.” Frontiers in immunology (2026). PMID: 42317308 ↗
L4SR_OBSCited in: Clinical Presentation, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[126]
Hoorn EJ, Zietse R. “Diagnosis and Treatment of Hyponatremia: Compilation of the Guidelines.” Journal of the American Society of Nephrology : JASN (2017). PMID: 28174217 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders
[127]
Atila C, Camerin SJ, Maleska Maceski A et al.. “Neurofilament light chain and glial fibrillary acidic protein as potential early indicators of osmotic brain stress in hyponatremia and its correction.” European journal of endocrinology (2026). PMID: 42299484 ↗
L4RCTCited in: Clinical Presentation, Diagnosis and Workup, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment
[128]
Reuter S, Scholten N, Pavenstädt H et al.. “Hyponatremia and seizures caused by triamcinolone-induced adrenal insufficiency.” Nature reviews. Nephrology (2010). PMID: 20111051 ↗
L4CASE_REPORTCited in: Clinical Presentation, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae)
[129]
Sterns RH, Rondon-Berrios H, Adrogué HJ et al.. “Treatment Guidelines for Hyponatremia: Stay the Course.” Clinical journal of the American Society of Nephrology : CJASN (2023). PMID: 37379081 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment
[130]
Sterns RH. “Treatment of Severe Hyponatremia.” Clinical journal of the American Society of Nephrology : CJASN (2018). PMID: 29295830 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[131]
Decaux G, Musch W. “Clinical laboratory evaluation of the syndrome of inappropriate secretion of antidiuretic hormone.” Clinical journal of the American Society of Nephrology : CJASN (2008). PMID: 18434618 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Diagnosis and Workup, Complications (Chronic Systemic Sequelae)
[132]
Spasovski G. “Hyponatraemia-treatment standard 2024.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2024). PMID: 39009016 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[133]
Gungor O, Aydin Z, Inci A et al.. “Seizures in patients with kidney diseases: a neglected problem?” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2023). PMID: 34596683 ↗
L5REVIEW_NARRATIVECited in: Clinical Presentation, Acute Management, Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Renal Replacement Therapy, Dialysis Access & Transplantation, Special Populations & Pregnancy
[134]
Fremont D, Buh A, Hoar-Stephens C et al.. “Eating disorder-related electrolyte abnormalities and adverse outcomes: A systematic review and meta-analysis.” PloS one (2026). PMID: 42224161 ↗
L1SR_OBSCited in: Clinical Presentation
[135]
Huang J, Cai J, Cheng W et al.. “Clinical characteristics, management, and prognosis of pembrolizumab-induced hypophysitis: retrospective analysis based on case reports.” Frontiers in immunology (2026). PMID: 42358986 ↗
L4CASE_REPORTCited in: Clinical Presentation, Diagnosis and Workup, Fluid, Electrolyte & Acid-Base Disorders
[136]
Zhang R, Zhang Y, Nie Y et al.. “Coexistence of 21-hydroxylase deficiency and Gitelman syndrome in a neonate presenting with severe hyponatremic seizures: a case report.” Frontiers in endocrinology (2026). PMID: 42358677 ↗
L4CASE_REPORTCited in: Clinical Presentation, Fluid, Electrolyte & Acid-Base Disorders
[137]
Ishii T, Shindo J, Hashimoto N et al.. “GnRH Analog followed by Sex Hormone Therapy as a Preventive Strategy against Ovarian Complications in Congenital Lipoid Adrenal Hyperplasia: A Case Report.” Hormone research in paediatrics (2026). PMID: 42301958 ↗
L4CASE_REPORTCited in: Clinical Presentation
[138]
Lin F, Tang X, Fei X et al.. “Successful treatment by high dose glucocorticoid of miliary tuberculosis complicated with acute respiratory distress syndrome: a case report.” BMC infectious diseases (2026). PMID: 42265561 ↗
L4CASE_REPORTCited in: Clinical Presentation, Diagnosis and Workup, History and Evolution of Treatment
[139]
Pazhayattil GS, Rastegar A, Brewster UC. “Approach to the diagnosis and treatment of hyponatremia in pregnancy.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2014). PMID: 25542410 ↗
L4CASE_REPORTCited in: Diagnosis and Workup, Special Populations & Pregnancy
[140]
Greenberg JH, Tufro A, Marsenic O. “Approach to the treatment of the infant with hyponatremia.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2014). PMID: 25542409 ↗
L4CASE_REPORTCited in: Diagnosis and Workup
[141]
Rosner MH, Perazella MA, Choi MJ. “American Society of Nephrology Quiz and Questionnaire 2015: Electrolytes and Acid-Base Disorders.” Clinical journal of the American Society of Nephrology : CJASN (2016). PMID: 26825098 ↗
L5CASE_REPORTCited in: Diagnosis and Workup, Long-term and Definitive Management, Complications (Chronic Systemic Sequelae)
[142]
Savelberg ABMC, Hoorn EJ, Refardt JC. “Management of Chronic Hyponatremia in the Outpatient Setting.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2025). PMID: 41093160 ↗
L5REVIEW_NARRATIVECited in: Diagnosis and Workup
[143]
Chen JJ, Lee TH, Lai PC et al.. “Efficacy of Desmopressin for Post-Kidney Biopsy Bleeding Complications Prevention: A Systematic Review With Frequentist and Bayesian Meta-Analysis.” Nephrology (Carlton, Vic.) (2026). PMID: 41531175 ↗
L1SR_OBSCited in: Diagnosis and Workup
[144]
Rafat C, Schortgen F, Gaudry S et al.. “Use of desmopressin acetate in severe hyponatremia in the intensive care unit.” Clinical journal of the American Society of Nephrology : CJASN (2013). PMID: 24262506 ↗
L4OTHERCited in: Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Long-term and Definitive Management
[145]
Salahudeen AK, Doshi SM, Pawar T et al.. “Incidence rate, clinical correlates, and outcomes of AKI in patients admitted to a comprehensive cancer center.” Clinical journal of the American Society of Nephrology : CJASN (2012). PMID: 23243268 ↗
L2OTHERCited in: Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation, Prevention, Screening & Surveillance
[146]
Amanzholova A, Morenko M, Ashim K et al.. “Modifiable risk factors in type 1 cardiorenal syndrome in children with congenital heart disease: a retrospective cohort study.” BMC cardiovascular disorders (2026). PMID: 41749107 ↗
L2COHORTCited in: Diagnosis and Workup, Staging and Risk Stratification (KDIGO), Acute Management, Complications (Chronic Systemic Sequelae)
[147]
Woo HY, Jung K, Lee KH et al.. “Incidence, risk factors, and clinical impact of hyponatremia in pediatric trauma: a 9-year retrospective cohort study.” BMC pediatrics (2026). PMID: 41634650 ↗
L2COHORTCited in: Diagnosis and Workup, Acute Management, Complications (Chronic Systemic Sequelae)
[148]
Chen L, Gu T, Gao W et al.. “Clinical profile and predictors of guillain-barre syndrome associated pneumonia: a retrospective cohort study.” BMC neurology (2026). PMID: 41612234 ↗
L2COHORTCited in: Diagnosis and Workup, Complications (Chronic Systemic Sequelae)
[149]
Long Z, Zeng S. “A case report of syndrome of inappropriate antidiuretic hormone secretion unveiling hypothalamic involvement in multiple system atrophy.” Frontiers in endocrinology (2026). PMID: 42181179 ↗
L4CASE_REPORTCited in: Diagnosis and Workup
[150]
Rudolphi CF, Musterd-Bhaggoe U, Ruijter GJG et al.. “The urine metabolomic signature of distal diuretics and diuretic-induced hyponatremia in patients with chronic kidney disease.” American journal of physiology. Renal physiology (2026). PMID: 41962959 ↗
L2RCTCited in: Diagnosis and Workup
[151]
Kumar G, Zahid I, Lager C et al.. “Disseminated histoplasmosis presenting as primary adrenal insufficiency in an immunocompetent host in the United States: a case report.” BMC infectious diseases (2026). PMID: 41935290 ↗
L4CASE_REPORTCited in: Diagnosis and Workup
[152]
Sun C, Sun G, Chen K et al.. “Refractory hyponatremia mimicking worsening depression after suspected dimethoate exposure, influenza B infection, and venlafaxine up-titration: a case report.” BMC psychiatry (2026). PMID: 41904406 ↗
L4CASE_REPORTCited in: Diagnosis and Workup
[153]
Bao S, Qin L, Zhang Y et al.. “Refractory hyponatremia in small cell lung cancer: a case report and literature review.” Frontiers in endocrinology (2026). PMID: 41890180 ↗
L4CASE_REPORTCited in: Diagnosis and Workup
[154]
Mazzeo A, Alaimo V, Grimaldi LM. “Probable tirzepatide-associated limbic encephalitis with status epilepticus in a patient with extreme obesity: a case report.” Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology (2026). PMID: 41882230 ↗
L4CASE_REPORTCited in: Diagnosis and Workup
[155]
Verbalis JG, Ellison H, Hobart M et al.. “Tolvaptan and Neurocognitive Function in Mild to Moderate Chronic Hyponatremia: A Randomized Trial (INSIGHT).” American journal of kidney diseases : the official journal of the National Kidney Foundation (2016). PMID: 26874645 ↗
L1RCTCited in: Staging and Risk Stratification (KDIGO), Long-term and Definitive Management, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[156]
Refardt J, Imber C, Sailer CO et al.. “A Randomized Trial of Empagliflozin to Increase Plasma Sodium Levels in Patients with the Syndrome of Inappropriate Antidiuresis.” Journal of the American Society of Nephrology : JASN (2020). PMID: 32019783 ↗
L1RCTCited in: Staging and Risk Stratification (KDIGO), Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[157]
Sterns RH, Hix JK, Silver S. “Treating profound hyponatremia: a strategy for controlled correction.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2010). PMID: 20709440 ↗
L4CASE_REPORTCited in: Staging and Risk Stratification (KDIGO)
[158]
Yessayan L, Yee J, Frinak S et al.. “Treatment of severe hyponatremia in patients with kidney failure: role of continuous venovenous hemofiltration with low-sodium replacement fluid.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2014). PMID: 24792353 ↗
L4CASE_REPORTCited in: Staging and Risk Stratification (KDIGO), Renal Replacement Therapy, Dialysis Access & Transplantation
[159]
Liu C, Jin B, Liu Y et al.. “Construction of the prognostic model for small-cell lung cancer based on inflammatory markers: A real-world study of 612 cases with eastern cooperative oncology group performance score 0-1.” Cancer medicine (2023). PMID: 37015898 ↗
L2RCTCited in: Staging and Risk Stratification (KDIGO)
[160]
Kashani M, Wei L, Singh W et al.. “Serum chloride concentrations and outcomes in adult patients with cirrhosis: a systematic review and meta-analysis.” BMC nephrology (2025). PMID: 41013381 ↗
L1SR_OBSCited in: Staging and Risk Stratification (KDIGO)
[161]
Mumbulu ET, Nkodila AN, Saint-Joy V et al.. “Survival and predictors of mortality in patients with heart failure in the cardiology department of the Center Hospitalier Basse Terre in Guadeloupe: historical cohort study.” BMC cardiovascular disorders (2024). PMID: 39468485 ↗
L2COHORTCited in: Staging and Risk Stratification (KDIGO)
[162]
Dutta D, Kumar M, Joshi A et al.. “Safety of Rapid Intermittent Bolus versus Slow Continuous Infusion of Hypertonic Saline for Managing Symptomatic Severe Hyponatremia: A Systematic Review and Meta-analysis.” Annals of African medicine (2025). PMID: 40053429 ↗
L1SR_OBSCited in: Staging and Risk Stratification (KDIGO)
[163]
Sahmeddini MA, Afshari M, Khosravi MB et al.. “Association Between Preoperative Hyponatremia and Survival After Liver Transplant: A Systematic Review and Meta-Analysis.” Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation (2024). PMID: 39072515 ↗
L1SR_OBSCited in: Staging and Risk Stratification (KDIGO)
[164]
Goudsmit BFJ, Putter H, Tushuizen ME et al.. “Validation of the Model for End-stage Liver Disease sodium (MELD-Na) score in the Eurotransplant region.” American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons (2020). PMID: 32529758 ↗
L2OTHERCited in: Staging and Risk Stratification (KDIGO), Fluid, Electrolyte & Acid-Base Disorders
[165]
Al Yaqoubi IH, Al-Maqbali JS, Al Farsi AA et al.. “Prevalence of hyponatremia among medically hospitalized patients and associated outcomes: a retrospective cohort study.” Annals of Saudi medicine (2024). PMID: 39368118 ↗
L2COHORTCited in: Staging and Risk Stratification (KDIGO)
[166]
Jia H, Zheng Q, Zhang L et al.. “Perioperative hyperchloremia is associated with acute kidney injury in elderly patients undergoing bipolar plasmakinetic transurethral resection of the prostate: a prospective observational study.” World journal of urology (2026). PMID: 42189243 ↗
L2OTHERCited in: Staging and Risk Stratification (KDIGO)
[167]
Ahluwalia AS, Ramesh H, Asad Z et al.. “Assessing the Association of Age and Preoperative Sodium Level on Colectomy Outcomes: An NSQIP Study.” The Journal of surgical research (2026). PMID: 41687140 ↗
L2OTHERCited in: Staging and Risk Stratification (KDIGO)
[168]
Subhash C, Chander S, Latif R et al.. “Clinical Outcomes of Patients undergoing Hemodialysis with Cool versus Standard Dialysate: A Systematic Review and Meta-Analysis.” American journal of nephrology (2025). PMID: 40031875 ↗
L1SR_OBSCited in: Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation
[169]
Waskowski J, Salvato SM, Müller M et al.. “Choice of creep or maintenance fluid type and their impact on total daily ICU sodium burden in critically ill patients: A systematic review and meta-analysis.” Journal of critical care (2023). PMID: 37651780 ↗
L1SR_OBSCited in: Acute Management
[170]
Amemiya Y, Hisamune R, Yamakawa K et al.. “Serum sodium trajectories impact clinical outcomes in extracorporeal resuscitation of cardiac arrest: A multicenter retrospective cohort study.” Resuscitation plus (2025). PMID: 40978015 ↗
L2COHORTCited in: Acute Management, Prognosis and Natural History
[171]
Wang D, Zhang F, Pan J et al.. “Influencing factors for surgical treatment in neonatal necrotizing enterocolitis: a systematic review and meta-analysis.” BMC pediatrics (2024). PMID: 39123165 ↗
L1SR_OBSCited in: Acute Management
[172]
Pinter J, Genser B, Moissl U et al.. “Hyponatraemia and fluid overload are associated with higher risk of mortality in dialysis patients.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2023). PMID: 36861328 ↗
L2OTHERCited in: Acute Management, Fluid, Electrolyte & Acid-Base Disorders, Renal Replacement Therapy, Dialysis Access & Transplantation, Complications (Chronic Systemic Sequelae), Prognosis and Natural History, Special Populations & Pregnancy, Prevention, Screening & Surveillance
[173]
Pan Y, Li D, Zhang Z et al.. “Clinical characteristics and outcomes of maintenance hemodialysis patients with COVID-19 during the Omicron wave of the pandemic in Beijing: a single center retrospective study.” BMC nephrology (2024). PMID: 38649863 ↗
L2COHORTCited in: Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation
[174]
Harrison NE, Ehrman R, Collins S et al.. “The prognostic value of improving congestion on lung ultrasound during treatment for acute heart failure differs based on patient characteristics at admission.” Journal of cardiology (2023). PMID: 37579872 ↗
L2TRIAL_NONRANDOMCited in: Acute Management
[175]
Singh A, Pursnani L, Mahapatra HS et al.. “Comparing Concurrent and Countercurrent Dialysate Flow in Hemodialysis: A Pilot Study on Hyponatremic Patients.” Seminars in dialysis (2025). PMID: 40916046 ↗
L1RCTCited in: Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation
[176]
Yusuf B, Ediamu T, Odoch S et al.. “Electrolyte imbalance in Asphyxiated term neonates: Incidence, predictors, and outcomes from a prospective cohort study in Northern Uganda.” PloS one (2026). PMID: 42241433 ↗
L2COHORTCited in: Acute Management
[177]
Dahiya A, Goel S, Saha A et al.. “Transient antenatal Bartter syndrome type 5 presenting as shock and metabolic acidosis in a preterm neonate.” Pediatric nephrology (Berlin, Germany) (2026). PMID: 41711945 ↗
L4CASE_REPORTCited in: Acute Management
[178]
Karakadze M, Sugar S, Teitelbaum I. “Icodextrin lowers serum sodium in dose-dependent fashion: A case report.” Peritoneal dialysis international : journal of the International Society for Peritoneal Dialysis (2025). PMID: 40740020 ↗
L4CASE_REPORTCited in: Acute Management, Renal Replacement Therapy, Dialysis Access & Transplantation
[179]
Abraham WT, Hensen J, Gross PA et al.. “Lixivaptan safely and effectively corrects serum sodium concentrations in hospitalized patients with euvolemic hyponatremia.” Kidney international (2012). PMID: 22932119 ↗
L1RCTCited in: Long-term and Definitive Management, History and Evolution of Treatment, Special Populations & Pregnancy
[180]
Chander S, Kumari R, Lohana AC et al.. “Urea to Treat Hyponatremia Due to Syndrome of Inappropriate Antidiuretic Hormone Secretion: A Systematic Review and Meta-Analysis.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2024). PMID: 39362395 ↗
L2SR_OBSCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[181]
Rozen-Zvi B, Yahav D, Gheorghiade M et al.. “Vasopressin receptor antagonists for the treatment of hyponatremia: systematic review and meta-analysis.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2010). PMID: 20538391 ↗
L1SR_OBSCited in: Long-term and Definitive Management
[182]
Krisanapan P, Vongsanim S, Pin-On P et al.. “Efficacy of Furosemide, Oral Sodium Chloride, and Fluid Restriction for Treatment of Syndrome of Inappropriate Antidiuresis (SIAD): An Open-label Randomized Controlled Study (The EFFUSE-FLUID Trial).” American journal of kidney diseases : the official journal of the National Kidney Foundation (2020). PMID: 32199708 ↗
L1RCTCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Special Populations & Pregnancy
[183]
Refardt J, Imber C, Nobbenhuis R et al.. “Treatment Effect of the SGLT2 Inhibitor Empagliflozin on Chronic Syndrome of Inappropriate Antidiuresis: Results of a Randomized, Double-Blind, Placebo-Controlled, Crossover Trial.” Journal of the American Society of Nephrology : JASN (2022). PMID: 36396331 ↗
L1RCTCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Special Populations & Pregnancy
[184]
Berl T, Quittnat-Pelletier F, Verbalis JG et al.. “Oral tolvaptan is safe and effective in chronic hyponatremia.” Journal of the American Society of Nephrology : JASN (2010). PMID: 20185637 ↗
L2RCTCited in: Long-term and Definitive Management, History and Evolution of Treatment
[185]
Schrier RW, Gross P, Gheorghiade M et al.. “Tolvaptan, a selective oral vasopressin V2-receptor antagonist, for hyponatremia.” The New England journal of medicine (2006). PMID: 17105757 ↗
L1RCTCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[186]
Soupart A, Gross P, Legros JJ et al.. “Successful long-term treatment of hyponatremia in syndrome of inappropriate antidiuretic hormone secretion with satavaptan (SR121463B), an orally active nonpeptide vasopressin V2-receptor antagonist.” Clinical journal of the American Society of Nephrology : CJASN (2006). PMID: 17699341 ↗
L1RCTCited in: Long-term and Definitive Management, History and Evolution of Treatment
[187]
Desai AC, Maalouf NM, Harper JD et al.. “Prevention of urinary stones with hydration: a randomised clinical trial of an adherence intervention.” Lancet (London, England) (2026). PMID: 41864748 ↗
L1RCTCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment
[188]
Wirth LJ, Sherman E, Robinson B et al.. “Efficacy of Selpercatinib in RET-Altered Thyroid Cancers.” The New England journal of medicine (2020). PMID: 32846061 ↗
L2TRIAL_NONRANDOMCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae), Prognosis and Natural History, Special Populations & Pregnancy
[189]
Drilon A, Oxnard GR, Tan DSW et al.. “Efficacy of Selpercatinib in RET Fusion-Positive Non-Small-Cell Lung Cancer.” The New England journal of medicine (2020). PMID: 32846060 ↗
L2TRIAL_NONRANDOMCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment, Complications (Chronic Systemic Sequelae), Prognosis and Natural History, Special Populations & Pregnancy
[190]
Von Hoff DD, LoRusso PM, Rudin CM et al.. “Inhibition of the hedgehog pathway in advanced basal-cell carcinoma.” The New England journal of medicine (2009). PMID: 19726763 ↗
L2TRIAL_NONRANDOMCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[191]
Soupart A, Coffernils M, Couturier B et al.. “Efficacy and tolerance of urea compared with vaptans for long-term treatment of patients with SIADH.” Clinical journal of the American Society of Nephrology : CJASN (2012). PMID: 22403276 ↗
L2TRIAL_NONRANDOMCited in: Long-term and Definitive Management, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[192]
Bavbek N, Kargili A, Akcay A et al.. “Recurrent hyponatremia associated with citalopram and mirtazapine.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2006). PMID: 16997047 ↗
L4CASE_REPORTCited in: Long-term and Definitive Management, History and Evolution of Treatment
[193]
Gross PA, Wagner A, Decaux G. “Vaptans are not the mainstay of treatment in hyponatremia: perhaps not yet.” Kidney international (2011). PMID: 21451459 ↗
L5REVIEW_NARRATIVECited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae)
[194]
Erdélyi LS, Mann WA, Morris-Rosendahl DJ et al.. “Mutation in the V2 vasopressin receptor gene, AVPR2, causes nephrogenic syndrome of inappropriate diuresis.” Kidney international (2015). PMID: 26131744 ↗
L4OTHERCited in: Long-term and Definitive Management
[195]
Gankam Kengne F, Couturier BS, Soupart A et al.. “Urea minimizes brain complications following rapid correction of chronic hyponatremia compared with vasopressin antagonist or hypertonic saline.” Kidney international (2014). PMID: 25100046 ↗
L5OTHERCited in: Long-term and Definitive Management, Complications (Chronic Systemic Sequelae)
[196]
Rosner MH. “Lixivaptan: a vasopressin receptor antagonist for the treatment of hyponatremia.” Kidney international (2012). PMID: 23151986 ↗
L5OTHERCited in: Long-term and Definitive Management
[197]
Pham PC, Pham PM, Pham PT. “Vasopressin excess and hyponatremia.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2006). PMID: 16632011 ↗
L5REVIEW_NARRATIVECited in: Long-term and Definitive Management
[198]
Lehrich RW, Greenberg A. “When is it appropriate to use vasopressin receptor antagonists?” Journal of the American Society of Nephrology : JASN (2008). PMID: 18337478 ↗
L5OTHERCited in: Long-term and Definitive Management
[199]
Suzuki H, Sugimura Y, Iwama S et al.. “Minocycline prevents osmotic demyelination syndrome by inhibiting the activation of microglia.” Journal of the American Society of Nephrology : JASN (2010). PMID: 21030598 ↗
L5OTHERCited in: Long-term and Definitive Management, Complications (Chronic Systemic Sequelae), Prognosis and Natural History
[200]
Decaux G, Vandergheynst F, Bouko Y et al.. “Nephrogenic syndrome of inappropriate antidiuresis in adults: high phenotypic variability in men and women from a large pedigree.” Journal of the American Society of Nephrology : JASN (2007). PMID: 17229917 ↗
L4OTHERCited in: Long-term and Definitive Management, Special Populations & Pregnancy
[201]
Refardt J, Potasso L, Pelouto A et al.. “A Randomized Trial of Targeted Hyponatremia Correction in Hospitalized Patients.” NEJM evidence (2026). PMID: 41733398 ↗
L1RCTCited in: Long-term and Definitive Management, History and Evolution of Treatment, Special Populations & Pregnancy
[202]
Sheng X, Huang G, Fang M et al.. “Toripalimab vs Dacarbazine as First-Line Therapy for Advanced Melanoma of Acral Subtype: The Phase 3 MELATORCH Randomized Clinical Trial.” JAMA oncology (2026). PMID: 41481311 ↗
L1RCTCited in: Long-term and Definitive Management, Prognosis and Natural History, Special Populations & Pregnancy
[203]
Uppal NN, Workeneh BT, Rondon-Berrios H et al.. “Electrolyte and Acid-Base Disorders Associated with Cancer Immunotherapy.” Clinical journal of the American Society of Nephrology : CJASN (2022). PMID: 35063968 ↗
L5REVIEW_NARRATIVECited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders
[204]
Rondon-Berrios H, Tandukar S, Mor MK et al.. “Urea for the Treatment of Hyponatremia.” Clinical journal of the American Society of Nephrology : CJASN (2018). PMID: 30181129 ↗
L4OTHERCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, Special Populations & Pregnancy
[205]
Perianayagam A, Sterns RH, Silver SM et al.. “DDAVP is effective in preventing and reversing inadvertent overcorrection of hyponatremia.” Clinical journal of the American Society of Nephrology : CJASN (2008). PMID: 18235152 ↗
L4OTHERCited in: Long-term and Definitive Management
[206]
Pelouto A, Monnerat S, Refardt J et al.. “Clinical factors associated with hyponatremia correction during treatment with oral urea.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2025). PMID: 39013606 ↗
L3OTHERCited in: Long-term and Definitive Management, Fluid, Electrolyte & Acid-Base Disorders, History and Evolution of Treatment
[207]
Karama M, Qaid M, Alkhammar A et al.. “Risk of urinary adverse effects of bevacizumab therapy in patients with ovarian cancer: a systematic review and meta-analysis.” Archivio italiano di urologia, andrologia : organo ufficiale [di] Societa italiana di ecografia urologica e nefrologica (2025). PMID: 41496682 ↗
L1SR_OBSCited in: Long-term and Definitive Management
[208]
Ibarra F, Hsu J, Jassal A et al.. “Comparison of 8.4% Sodium Bicarbonate vs. 3% Sodium Chloride in Severe Hyponatremia: A Retrospective Cohort Study.” Academic emergency medicine : official journal of the Society for Academic Emergency Medicine (2026). PMID: 41937305 ↗
L3COHORTCited in: Long-term and Definitive Management, Special Populations & Pregnancy
[209]
Idemitsu R, Nagai T, Matsui H et al.. “Risk factors for adverse events associated with trimethoprim-sulfamethoxazole treatment for Pneumocystis pneumonia in non-human immunodeficiency virus-infected patients: a multicenter, retrospective, observational cohort study.” BMC infectious diseases (2026). PMID: 41559609 ↗
L3COHORTCited in: Long-term and Definitive Management, Special Populations & Pregnancy
[210]
Jung K, Kim JH, Hyeon DE et al.. “Antidepressants and the risk of hyponatremia: A multi-institutional cohort study using observational medical outcomes partnership-Common Data Model.” British journal of clinical pharmacology (2026). PMID: 41531184 ↗
L3COHORTCited in: Long-term and Definitive Management, Special Populations & Pregnancy
[211]
Gholipour F, Bahrami Samani H, Assadi A et al.. “Prophylactic Intravenous Furosemide for Reducing Hyponatremia Risk in Monopolar Transurethral Prostate Surgery: A Randomized Clinical Trial.” Iranian journal of medical sciences (2025). PMID: 41158838 ↗
L1RCTCited in: Long-term and Definitive Management
[212]
Greenberg A, Verbalis JG, Amin AN et al.. “Current treatment practice and outcomes. Report of the hyponatremia registry.” Kidney international (2015). PMID: 25671764 ↗
L2OTHERCited in: Fluid, Electrolyte & Acid-Base Disorders, Special Populations & Pregnancy
[213]
Stanajic-Petrovic G, Keck M, Barbe P et al.. “A Snake Toxin Derivative for Treatment of Hyponatremia and Polycystic Kidney Diseases.” Journal of the American Society of Nephrology : JASN (2024). PMID: 39431458 ↗
L5OTHERCited in: Fluid, Electrolyte & Acid-Base Disorders
[214]
Böger CA, Gorski M, McMahon GM et al.. “NFAT5 and SLC4A10 Loci Associate with Plasma Osmolality.” Journal of the American Society of Nephrology : JASN (2017). PMID: 28360221 ↗
L2OTHERCited in: Fluid, Electrolyte & Acid-Base Disorders, Special Populations & Pregnancy
[215]
Wang H, Fang S, Wang H et al.. “Association between serum calcium and in-hospital mortality in patients with severe fever with thrombocytopenia syndrome: a retrospective cohort study.” Virology journal (2026). PMID: 42415094 ↗
L3COHORTCited in: Fluid, Electrolyte & Acid-Base Disorders
[216]
Xi C, Wan M, Wu H et al.. “Preoperative hyponatremia is associated with increased postoperative complications and short- to long-term mortality in geriatric hip fracture patients: a retrospective cohort study.” BMC geriatrics (2026). PMID: 42323552 ↗
L3COHORTCited in: Fluid, Electrolyte & Acid-Base Disorders, Prognosis and Natural History
[217]
Marroquin MV, Sy J, Kleine CE et al.. “Association of pre-ESKD hyponatremia with post-ESKD outcomes among incident ESKD patients.” Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (2022). PMID: 34390572 ↗
L3OTHERCited in: Fluid, Electrolyte & Acid-Base Disorders, Complications (Chronic Systemic Sequelae), Prognosis and Natural History, Special Populations & Pregnancy
[218]
Zhang Y, Zhang J, Jing R. “Risk of antidepressant-induced hyponatremia in geriatric patients: a systematic review and meta-analysis.” BMC geriatrics (2026). PMID: 42374213 ↗
L1SR_OBSCited in: Fluid, Electrolyte & Acid-Base Disorders
[219]
Ashraf S, Wani SA, Burhan M et al.. “Safety and Efficacy of Lorundrostat in Uncontrolled Hypertension: A Systematic Review and Meta-Analysis.” Journal of cardiovascular pharmacology (2026). PMID: 42407042 ↗
L1SR_OBSCited in: Fluid, Electrolyte & Acid-Base Disorders
[220]
Lins PRG, Uvinha F, Passos FS et al.. “Proactive desmopressin for the prevention of serum sodium overcorrection in moderate-to-severe hyponatremia: a systematic review and meta-analysis.” BMC nephrology (2026). PMID: 42351030 ↗
L1SR_OBSCited in: Fluid, Electrolyte & Acid-Base Disorders
[221]
Devanita S LA, Adhyatma IGR, Cahya KKD. “Risk factors of cerebral vasospasm associated with ruptured arterio-venous malformation: A systematic review and meta-analysis.” Journal of cerebrovascular and endovascular neurosurgery (2026). PMID: 42374993 ↗
L1SR_OBSCited in: Fluid, Electrolyte & Acid-Base Disorders
[222]
Raharja H, Sungkar T, Ilhamd I. “Clinical and Laboratory Factors Associated With In-Hospital Mortality Among Patients With Decompensated Liver Cirrhosis: A Retrospective Study From Indonesia.” Cureus (2026). PMID: 42422636 ↗
L3COHORTCited in: Fluid, Electrolyte & Acid-Base Disorders
[223]
Wang Y, Zhang P. “Immune checkpoint inhibitor-induced hypopituitarism presenting as postoperative hyponatremia in a gastric cancer patient: a case report.” Frontiers in medicine (2026). PMID: 42383055 ↗
L4CASE_REPORTCited in: Fluid, Electrolyte & Acid-Base Disorders
[224]
Stewart D, Iancu D, Ashton E et al.. “Transplantation of a Gitelman Syndrome Kidney Ameliorates Hypertension: A Case Report.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2018). PMID: 30201548 ↗
L4CASE_REPORTCited in: Renal Replacement Therapy, Dialysis Access & Transplantation, Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[225]
Venkataraman K, McTaggart SJ, Collins MG. “Choosing fluids to reduce the risks of acute electrolyte disturbances in children after a kidney transplant.” Kidney international (2024). PMID: 38245215 ↗
L5OTHERCited in: Renal Replacement Therapy, Dialysis Access & Transplantation, Special Populations & Pregnancy
[226]
Pack S, Lee J. “Randomised controlled trial of a smartphone application-based dietary self-management program on haemodialysis patients.” Journal of clinical nursing (2021). PMID: 33377565 ↗
L1RCTCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[227]
Bhatt GC, Sethi SK, Mehta I et al.. “Literature Review of the Efficacy of High-Volume Hemofiltration in Critically Ill Pediatric Patients.” Blood purification (2022). PMID: 35468595 ↗
L5SR_OBSCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[228]
Li J, Song P, Yang D et al.. “A Systematic Review and Meta-Analysis: Hyponatremia Predicted All-Cause and Cardiovascular Mortality in Dialysis Population.” Blood purification (2021). PMID: 34284380 ↗
L2SR_OBSCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[229]
Jung S, Kim J, Lee J et al.. “Effects of the Type of Intraoperative Fluid in Living Donor Kidney Transplantation: A Single-Center Retrospective Cohort Study.” Yonsei medical journal (2022). PMID: 35352890 ↗
L3COHORTCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[230]
Hellman T, Uusalo P, Järvisalo MJ. “Continuous hemodialysis with citrate anticoagulation and standard dialysate for managing acute kidney injury in patients with moderate to severe hyponatremia-A retrospective study.” Acta anaesthesiologica Scandinavica (2021). PMID: 33595109 ↗
L4COHORTCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[231]
Miyauchi T, Nishiwaki H, Mizukami A et al.. “Hyponatremia and mortality in patients undergoing maintenance hemodialysis: Systematic review and meta-analysis.” Seminars in dialysis (2023). PMID: 36929612 ↗
L2SR_OBSCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[232]
Iimori M, Kitani T, Shiotsu Y et al.. “Impact of peritoneal dialysis on weight gain in a patient with anorexia nervosa.” Peritoneal dialysis international : journal of the International Society for Peritoneal Dialysis (2025). PMID: 39748517 ↗
L4CASE_REPORTCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[233]
de Fijter CWH, Stachowska-Pietka J, Waniewski J et al.. “High Osmol Gap Hyponatremia Caused by Icodextrin: A Case Series Report.” American journal of nephrology (2023). PMID: 37579741 ↗
L4CASE_REPORTCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[234]
Berchtold L, Filzer A, Achermann R et al.. “Impact of Hyponatremia after Renal Transplantation on Decline of Renal Function, Graft Loss and Patient Survival: A Prospective Cohort Study.” Nutrients (2021). PMID: 34578871 ↗
L2COHORTCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[235]
Rajasegaran P, Dion R, Yassine H et al.. “Feasibility of strategies to manage dysnatremia in pediatric CKRT: a simulation study.” Pediatric nephrology (Berlin, Germany) (2025). PMID: 41372703 ↗
L5OTHERCited in: Renal Replacement Therapy, Dialysis Access & Transplantation
[236]
Clark BA, Shannon RP, Rosa RM et al.. “Increased susceptibility to thiazide-induced hyponatremia in the elderly.” Journal of the American Society of Nephrology : JASN (1994). PMID: 7849250 ↗
L2RCTCited in: History and Evolution of Treatment
[237]
Andreoli DC, Whittier WL. “Reset Osmostat: The Result of Chronic Desmopressin Abuse?” American journal of kidney diseases : the official journal of the National Kidney Foundation (2017). PMID: 28223002 ↗
L4CASE_REPORTCited in: History and Evolution of Treatment
[238]
Thaler SM, Teitelbaum I, Berl T. “"Beer potomania" in non-beer drinkers: effect of low dietary solute intake.” American journal of kidney diseases : the official journal of the National Kidney Foundation (1998). PMID: 9631849 ↗
L4CASE_REPORTCited in: History and Evolution of Treatment
[239]
Huang CH, Chou KJ, Lee PT et al.. “A case of lymphocytic hypophysitis with masked diabetes insipidus unveiled by glucocorticoid replacement.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2005). PMID: 15696461 ↗
L4CASE_REPORTCited in: History and Evolution of Treatment
[240]
Peitzman SJ. “The flame photometer as engine of nephrology: a biography.” American journal of kidney diseases : the official journal of the National Kidney Foundation (2010). PMID: 20418000 ↗
L5OTHERCited in: History and Evolution of Treatment
[241]
McJunkin JE, de los Reyes EC, Irazuzta JE et al.. “La Crosse encephalitis in children.” The New England journal of medicine (2001). PMID: 11248155 ↗
L4OTHERCited in: History and Evolution of Treatment
[242]
Almond CS, Shin AY, Fortescue EB et al.. “Hyponatremia among runners in the Boston Marathon.” The New England journal of medicine (2005). PMID: 15829535 ↗
L2OTHERCited in: History and Evolution of Treatment
[243]
Chuck SL, Sande MA. “Infections with Cryptococcus neoformans in the acquired immunodeficiency syndrome.” The New England journal of medicine (1989). PMID: 2671735 ↗
L3OTHERCited in: History and Evolution of Treatment
[244]
Forrest JN, Cox M, Hong C et al.. “Superiority of demeclocycline over lithium in the treatment of chronic syndrome of inappropriate secretion of antidiuretic hormone.” The New England journal of medicine (1978). PMID: 413037 ↗
L4OTHERCited in: History and Evolution of Treatment
[245]
Rus Prelog P, Kores Plesničar B, Zupan M et al.. “The value and risks of antidepressant therapy in Alzheimer's disease: a field update and its clinical implications.” Expert review of neurotherapeutics (2026). PMID: 41940797 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[246]
Nguyen M, Oh S, King M et al.. “Current Management of Resistant Hypertension in Patients with Intracerebral Hemorrhage.” International journal of molecular sciences (2026). PMID: 41898576 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[247]
Deshayes TA. “Beyond the one-size-fits-all hydration recommendation for older adults: a call for more research on age-related change in thirst and hydration behavior.” European journal of applied physiology (2026). PMID: 41774103 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[248]
Mehmandoost M, Bahri A, Akbarzadeh D et al.. “Hyponatremia in aneurysmal subarachnoid hemorrhage: A systematic review and meta-analysis on management approaches.” Neurocirugia (2026). PMID: 41730335 ↗
L2SR_OBSCited in: History and Evolution of Treatment
[249]
Johnson RJ, Lee SMK, Sánchez-Lozada LG et al.. “Fructose: A New Variable to Consider in SIADH and the Hyponatremia Associated With Long-Distance Running?” American journal of kidney diseases : the official journal of the National Kidney Foundation (2023). PMID: 36940740 ↗
L5OTHERCited in: Complications (Chronic Systemic Sequelae)
[250]
Bot KKIM, Heus R, Drenth JPH et al.. “Low-Dose vs. Standard Care Iv Human Albumin During Large-Volume Paracentesis in Patients With Liver Cirrhosis: A Systematic Review.” Liver international : official journal of the International Association for the Study of the Liver (2026). PMID: 41889150 ↗
L2SR_OBSCited in: Complications (Chronic Systemic Sequelae), Prognosis and Natural History
[251]
Schneider AR, Radu LM, Tang KL. “Outcomes with Sodium Overcorrection in Chronic Hyponatremia: A Systematic Review and Meta-analysis.” Journal of general internal medicine (2026). PMID: 41652262 ↗
L2SR_OBSCited in: Complications (Chronic Systemic Sequelae)
[252]
Yi Y, Fu X, Zhao Y et al.. “Psychiatric symptoms as clinical warning signals of adult anti-LGI-1 encephalitis: an observational cohort study.” BMC psychiatry (2026). PMID: 41928193 ↗
L2COHORTCited in: Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[253]
Khor WT, Wong CE, Chang Y et al.. “Effect of preoperative anemia on surgical outcomes in endonasal transsphenoidal surgery for pituitary adenoma: a matched-cohort study.” Acta neurochirurgica (2026). PMID: 41760831 ↗
L2COHORTCited in: Complications (Chronic Systemic Sequelae)
[254]
Mark DG, Alavi M, Nugent JR et al.. “Sodium Correction Rates and Associated Outcomes Among Patients With Severe Hyponatremia : A Retrospective Cohort Study.” Annals of internal medicine (2026). PMID: 41587479 ↗
L2COHORTCited in: Complications (Chronic Systemic Sequelae), Special Populations & Pregnancy
[255]
Mohmand HK, Issa D, Ahmad Z et al.. “Hypertonic saline for hyponatremia: risk of inadvertent overcorrection.” Clinical journal of the American Society of Nephrology : CJASN (2007). PMID: 17913972 ↗
L4OTHERCited in: Complications (Chronic Systemic Sequelae)
[256]
Turin CG, Kerr JM, Post KD et al.. “Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for the Role of Medical Perioperative Management for Patients With Functioning Pituitary Adenomas.” Neurosurgery (2025). PMID: 40815128 ↗
L1SR_OBSCited in: Prognosis and Natural History
[257]
Koyano K, Arai T, Toyoda H et al.. “Prognostic Value of an Early Response to Tolvaptan and Its Clinical Implications in Patients With Cirrhosis and Hepatic Edema: A Nationwide Multicenter Cohort Study.” Hepatology research : the official journal of the Japan Society of Hepatology (2026). PMID: 41653074 ↗
L2COHORTCited in: Prognosis and Natural History
[258]
Netzer S, Gastens V, Boland B et al.. “Association Between Hyponatremia and Mortality and Readmission in Multimorbid Older Adults-A Cohort Study.” Journal of clinical medicine (2025). PMID: 41156016 ↗
L2COHORTCited in: Prognosis and Natural History
[259]
Khajuria R, Jindal A, Sharma MK et al.. “Efficacy and Safety of Carvedilol in Cirrhosis Patients With New-Onset Uncomplicated Ascites Without High-Risk Esophageal Varices (CARVE-AS Trial).” The American journal of gastroenterology (2025). PMID: 40689908 ↗
L1RCTCited in: Prognosis and Natural History
[260]
Kulkarni AV, Maiwall R, Arora V et al.. “Addition of midodrine to albumin reduces the incidence of complications of large-volume paracentesis: an RCT comparing midodrine, terlipressin, and albumin.” Hepatology international (2025). PMID: 40614032 ↗
L1RCTCited in: Prognosis and Natural History
[261]
Lau BSR, Chua NYM, Ong WT et al.. “Paraneoplastic Syndromes in Gallbladder Cancer: A Systematic Review.” Medicina (Kaunas, Lithuania) (2025). PMID: 40142228 ↗
L4SR_OBSCited in: Prognosis and Natural History
[262]
Fenske WK, Christ-Crain M, Hörning A et al.. “A copeptin-based classification of the osmoregulatory defects in the syndrome of inappropriate antidiuresis.” Journal of the American Society of Nephrology : JASN (2014). PMID: 24722436 ↗
L4OTHERCited in: Special Populations & Pregnancy
[263]
Wang B, Bonkovsky HL, Lim JK et al.. “AGA Clinical Practice Update on Diagnosis and Management of Acute Hepatic Porphyrias: Expert Review.” Gastroenterology (2023). PMID: 36642627 ↗
L1GUIDELINECited in: Prevention, Screening & Surveillance
[264]
Ashritha A, Lal BB, Khanna R et al.. “Midodrine reduces new-onset acute kidney injury and hyponatremia in children with cirrhosis and ascites awaiting liver transplantation: Results from an open-label RCT.” Journal of pediatric gastroenterology and nutrition (2023). PMID: 38374552 ↗
L1RCTCited in: Prevention, Screening & Surveillance
[265]
Singh V, Kumar P, Verma N et al.. “Propranolol vs. band ligation for primary prophylaxis of variceal hemorrhage in cirrhotic patients with ascites: a randomized controlled trial.” Hepatology international (2022). PMID: 35672572 ↗
L1RCTCited in: Prevention, Screening & Surveillance
[266]
Ren Y, Li S, Lei JJ et al.. “Clinical feature and genetic analysis of HMBS gene in Chinese patients with acute intermittent porphyria: a systematic review.” Frontiers in genetics (2023). PMID: 38148975 ↗
L4SR_OBSCited in: Prevention, Screening & Surveillance
[267]
Hata M, Okazaki Y, Tanabe S et al.. “Intravascular hemolysis as an initial complication of acute hyponatremia from water intoxication.” The American journal of emergency medicine (2025). PMID: 40764205 ↗
L4CASE_REPORTCited in: Prevention, Screening & Surveillance
[268]
Li H, Chen X, Chen L et al.. “Case report: Acute severe hyponatremia-induced seizures in a newborn: a community-acquired case and literature review.” Frontiers in pharmacology (2024). PMID: 38957388 ↗
L4CASE_REPORTCited in: Prevention, Screening & Surveillance
[269]
Pande V, Jadhav R, Ilyaz M et al.. “Dyselectrolytemia in Children With Severe Pneumonia: A Prospective Study.” Cureus (2024). PMID: 38468998 ↗
L2COHORTCited in: Prevention, Screening & Surveillance
[270]
Sekhon SS, Taha K, Kim LH et al.. “A Pediatric Case of Reninoma Presenting with Paraneoplastic Syndrome of Inappropriate Antidiuretic Hormone Secretion.” Hormone research in paediatrics (2023). PMID: 38052189 ↗
L4CASE_REPORTCited in: Prevention, Screening & Surveillance

Quick Reference

Overview and Recommendations

Background

Evaluation

Management

Board Review — High Yield

Deep Dive — Evidence Details

Definition, Classification and Nomenclature

Synonyms and Abbreviations

Classification by Duration

Classification by Severity

Classification by Volume Status

Nomenclature of Specific Syndromes

Pathophysiology and Mechanism

The Renal Tubular Effector: Aquaporin-2 and the Collecting Duct

Brain Adaptation and the Risk of Osmotic Demyelination

Specific Pathophysiologic Pathways

Epidemiology, Etiology and Risk Factors

Demographic and Temporal Patterns

Risk Factors

Special Considerations

Clinical Presentation

Presenting Symptoms

Neurological Examination Findings

Phenotypic Variants

Red Flags

Atypical Presentations

Diagnosis and Workup

Step 1: Confirm Hypotonic Hyponatremia

Step 2: Assess Volume Status

Step 3: Urine Studies

Step 4: Additional Diagnostic Tests

Special Considerations

Imaging

Biopsy/Histology

Staging and Risk Stratification

Risk Stratification for Overcorrection

Prognostic Stratification and Mortality Risk

Tables

Acute Management

Step 1: Initial Assessment and Severity Classification

Step 2: First-Line Intervention for Severe Symptomatic Hyponatremia

Step 3: Second-Line and Adjunctive Management

Step 4: Monitoring and Titration

Step 5: Resolution and Transition to Long-Term Management

Drug/Modality Comparison Table

What NOT to Do

Controversies and Guideline Disagreement

Long-term and Definitive Management

Step 1: Identify Candidates for Chronic Therapy

Step 2: First-Line Therapy, Fluid Restriction and Urea

Step 3: Second-Line Options, Vaptans and SGLT2 Inhibitors

Step 4: Preventing Overcorrection, Risk Stratification and Rescue

Step 5: Transition and Monitoring

Drug/Modality Comparison

What NOT to Do

Controversies and Guideline Disagreement

Fluid, Electrolyte & Acid-Base Disorders

Potassium and Hyponatremia

Calcium, Magnesium, and Phosphate

Acid-Base Disturbances

Drug-Induced Multielectrolyte Disorders

Clinical Implications

Renal Replacement Therapy, Dialysis Access & Transplantation

RRT Modality Selection

Dialysate Sodium and Correction Rate

Transplantation

Controversies and Guideline Disagreement

History and Evolution of Treatment

Early Treatment: Fluid Restriction and the Thiazide Era

The Hypertonic Saline Controversy and the ODS Shadow

The Vaptan Revolution: SALT Trials and Beyond

Revisiting Non-Pharmacologic Options: The EFFUSE-FLUID Trial

Emerging Therapies: SGLT2 Inhibitors and Urea

The Targeted Correction Strategy: A Negative Trial

Controversies and Guideline Disagreement

Complications (Chronic Systemic Sequelae)

Osmotic Demyelination Syndrome (ODS)

Neuropsychiatric and Gait Impairments

(ODS)