title: Serotonin syndrome: a complex but easily avoidable condition.
abstract: Serotonin syndrome is a potentially life-threatening adverse drug reaction caused by excessive serotonergic agonism in central and peripheral nervous system serotonergic receptors (Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med 2005;352:1112-1120). Symptoms are characterized by a triad of neuron-excitatory features, which include (a) neuromuscular hyperactivity -- tremor, clonus, myoclonus, hyperreflexia and, in advanced stages, pyramidal rigidity; (b) autonomic hyperactivity -- diaphoresis, fever, tachycardia and tachypnea; (c) altered mental status -- agitation, excitement and, in advanced stages, confusion (Gillman PK. Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity. Br J Anaesth 2005;95:434-441). It arises when pharmacological agents increase serotonin neurotransmission at postsynaptic 5-hydroxytryptamine 1A and 5-hydroxytryptamine 2A receptors through increased serotonin synthesis, decreased serotonin metabolism, increased serotonin release, inhibition of serotonin reuptake or direct agonism of the serotonin receptors (Houlihan D. Serotonin syndrome resulting from coadministration of tramodol, venlafaxine, and mirtazapine. Ann Pharmacother 2004;38:411-413). The etiology is often the result of therapeutic drug use, intentional overdosing of serotonergic agents or complex interactions between drugs that directly or indirectly modulate the serotonin system (Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med 2005;352:1112-1120). Due to the increasing availability of agents with serotonergic activity, physicians need to more aware of serotonin syndrome. The following case highlights the complex nature in which serotonin syndrome can arise, as well as the proper recognition and treatment of a potentially life-threatening yet easily avoidable condition.
authors.affiliation: Department of Psychiatry, University of Massachusetts Medical School, Worcester, MA 01655, USA. dviry@ummhc.org
authors.forename: Yael
authors.initials: Y
authors.lastname: Dvir
authors.forename: Patrick
authors.initials: P
authors.lastname: Smallwood
mesh_terms: D018687:Antidepressive Agents, Second-Generation / Q000009:adverse effects* / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001008:Anxiety Disorders / Q000534:rehabilitation*; D001569:Benzodiazepines / Q000009:adverse effects* / Q000627:therapeutic use; D016642:Bupropion / Q000009:adverse effects* / Q000627:therapeutic use; D003511:Cyclohexanols / Q000009:adverse effects* / Q000627:therapeutic use; D003692:Delayed-Action Preparations; D003866:Depressive Disorder / Q000534:rehabilitation*; D004359:Drug Therapy, Combination; D005260:Female; D005473:Fluoxetine / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D008691:Methadone / Q000009:adverse effects* / Q000627:therapeutic use; D008875:Middle Aged; D000077152:Olanzapine; D009293:Opioid-Related Disorders / Q000534:rehabilitation*; D020230:Serotonin Syndrome / Q000175:diagnosis* / Q000517:prevention & control*; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D015819:Substance Abuse, Intravenous / Q000534:rehabilitation*; D000069470:Venlafaxine Hydrochloride
chemical_list: D018687:Antidepressive Agents, Second-Generation; D014150:Antipsychotic Agents; D001569:Benzodiazepines; D016642:Bupropion; D003511:Cyclohexanols; D003692:Delayed-Action Preparations; D005473:Fluoxetine; D008691:Methadone; D000077152:Olanzapine; D017367:Selective Serotonin Reuptake Inhibitors; D000069470:Venlafaxine Hydrochloride