Highlights & Basics
- Serotonin syndrome is the clinical manifestation of excess serotonin in the central nervous system, resulting from the therapeutic use or overdose of serotonergic drugs.
- Characterized by a triad of clinical features: neuromuscular excitation, autonomic effects, and altered mental status.
- Better described as a spectrum of toxicity, ranging from mild to severe, rather than a "syndrome".
- Diagnosis is clinical and should be based on the Hunter Serotonin Toxicity Criteria (HSTC), of which clonus is a key diagnostic feature.
- Treatment is guided by the severity of toxicity and involves cessation of the drug(s), supportive care, and antiserotonergic drugs in select patients.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Citations
Buckley NA, Dawson AH, Isbister GK. Serotonin syndrome. BMJ. 2014;348:g1626[Abstract]
Isbister GK, Buckley NA. The pathophysiology of serotonin toxicity in animals and humans: implications for diagnosis and treatment. Clin Neuropharmacol. 2005;28:205-214.[Abstract]
Dunkley EJ, Isbister GK, Sibbritt D, et al. The Hunter Serotonin Toxicity Criteria: simple and accurate diagnostic decision rules for serotonin toxicity. QJM. 2003;96:635-642.[Abstract][Full Text]
Chiew AL, Buckley NA. The serotonin toxidrome: shortfalls of current diagnostic criteria for related syndromes. Clin Toxicol (Phila). 2022 Feb;60(2):143-58.[Abstract]
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