Serotonin Syndrome

  • Mark Forrest GordonEmail author
  • Adena N. Leder
Part of the Current Clinical Neurology book series (CCNEU)


Serotonin syndrome presents with neuromuscular, autonomic, and mental status changes. Severe cases of serotonin syndrome, also called serotonin toxicity, are characterized by neuromuscular excitation (clonus, hyperreflexia, myoclonus, rigidity, tremor), autonomic stimulation (hyperthermia, tachycardia, tachypnea, diaphoresis, flushing), and altered mental state (anxiety, agitation, confusion). These more severe cases may come to the clinician’s attention on an emergency basis. The diagnosis of serotonin syndrome should be considered in a patient presenting with any combination of clonus, myoclonus, rigidity, and/or tremor. Serotonin syndrome is associated with the use of one or more serotonergic agents. Severe cases generally occur with combinations of serotonergic drugs, most commonly including a serotonin reuptake inhibitor and a monoamine oxidase inhibitor. Excessive serotonin (5-hydroxytryptamine) in the central nervous system has been implicated. Certain patient populations may be predisposed to developing serotonin toxicity, based on their use of various medications or other substances with serotonergic properties. When evaluating a patient with clinical features of neuromuscular excitation, autonomic stimulation, and/or altered mental state, prompt identification and management are critical, and treatment considerations are often complex.


Methylene Blue Neuroleptic Malignant Syndrome Serotonin Syndrome Serotonergic Neuron Serotonergic Agent 
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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Department of Medical AffairsBoehringer-Ingelheim Pharmaceuticals, IncRidgefieldUSA
  2. 2.Neurological Specialties of Long Island, LLPGreat NeckUSA

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