Pharmacogenetic workup of perioperative serotonin syndrome.

Serotonin syndrome is gaining attention in perioperative and chronic pain settings due to the growing prevalence of multimodal therapies that increase serotonin levels and thereby heighten patient risk. A patient's genetic make-up may further increase the risk of serotonin syndrome. A case of serotonin syndrome on emergence after general anesthesia is presented. A subsequent cytochrome P4502D6 genetic test result suggested a potential alteration in metabolism. For this patient, who was taking combination antidepressant medications and receiving common perioperative medicines, additive pharmacodynamic effects converged with a pharmacogenetic predisposition, resulting in serotonin syndrome.