Authors

Department of Clinical Toxicology, Isfahan Clinical Toxicology Research Center, Khorshid Hospital, Isfahan, Iran

Abstract

Serotonin toxicity is a common but often unrecognized toxicological condition. In 
most cases, a combination of two or more serotonergic drugs can cause serotonin 
syndrome. We describe a case of serotonin toxicity in a 17-year-old woman, 
secondary to suicidal ingestion of 1000 mg lamotrigine and 400 mg citalopram, 
which has been rarely reported. Our patient had a medical history of depression and 
was treated with lamotrigine and citalopram. She was brought to the emergency 
room with nausea, diaphoresis, agitation, shivering, tremor, vertigo, ataxia, 
mydriasis, nystagmus, hyperreflexia, myoclonus, tachycardia, tachypnea, and mild 
fever. The symptoms and signs were resolved within 3 days following hydration, 
sedation, and cyproheptadine. Minor cardiovascular symptoms are probably due 
to the less toxic dose of citalopram. Lamotrigine, especially in combination with 
other serotonergic drugs, should be considered a cause of serotonin toxicity.

Keywords

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