Serotonin syndrome in a child associated with erythromycin and sertraline

Serotonin syndrome is an uncommon, serious adverse reaction that is usually associated with the interaction of two or more serotonergic agents. A 12-year-old boy receiving sertraline developed the syndrome after erythromycin was added to his regimen. The proposed mechanism involves erythromycin inactivation of cytochrome P450 3A4 inhibition of sertraline metabolism, accumulation of the drug, and precipitation of the syndrome. It is important for clinicians to consider both pharmacokinetic and pharmacodynamic interactions to minimize the risk of the reaction.