Highlights & Basics
- Syndrome of inappropriate antidiuretic hormone (SIADH) is defined as euvolemic, hypotonic hyponatremia secondary to impaired free water excretion, usually from excessive arginine vasopressin (AVP) release.
- Severe neurologic symptoms, such as altered mental status, seizure, and coma, may result from SIADH and these are always treated with hypertonic saline, with close monitoring to avoid overcorrection of serum sodium.
- Central pontine myelinolysis (osmotic demyelination syndrome) may occur with rapid correction of serum sodium in excess of 12 mEq/L/day.
- Vasopressin receptor antagonists (also known as vaptans) are a class of medications that compete with the antidiuretic hormone AVP for binding at the vasopressin receptor, permitting free water excretion.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Citations
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Gross P. Clinical management of SIADH. Ther Adv Endocrinol Metab. 2012 Apr;3(2):61-73.[Abstract][Full Text]
Spasovski G, Vanholder R, Allolio B, et al. Clinical practice guideline on diagnosis and treatment of hyponatraemia. Eur J Endocrinol. 2014 Mar;170(3):G1-47.[Abstract][Full Text]
Ellison DH, Berl T. The syndrome of inappropriate antidiuresis. N Engl J Med. 2007 May 17;356(20):2064-72.[Abstract]
Hoorn EJ, Zietse R. Diagnosis and Treatment of Hyponatremia: Compilation of the Guidelines. J Am Soc Nephrol. 2017 May;28(5):1340-1349.[Abstract][Full Text]
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