Serotonin syndrome

Clinical manifestation of excess serotonin in the CNS, 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.

An excess of synaptic serotonin in the CNS that clinically manifests as the triad of neuromuscular excitation, autonomic effects, and altered mental status.[1]Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. 2005;352:1112-1120. http://www.ncbi.nlm.nih.gov/pubmed/15784664?tool=bestpractice.com Can result from therapeutic use of medications, drug overdose, or specific drug-drug interactions. It is better described as a spectrum of toxicity rather than a specific syndrome.[2]Buckley NA, Dawson AH, Isbister GK. Serotonin syndrome. BMJ. 2014;348:g1626 http://www.ncbi.nlm.nih.gov/pubmed/24554467?tool=bestpractice.com [3]Isbister GK, Buckley NA. The pathophysiology of serotonin toxicity in animals and humans: implications for diagnosis and treatment. Clin Neuropharmacol. 2005;28:205-214. http://www.ncbi.nlm.nih.gov/pubmed/16239759?tool=bestpractice.com Commonly known as serotonin toxicity.