Probable drug-drug interaction leading to serotonin syndrome in a patient treated with concomitant buspirone and linezolid in the setting of therapeutic hypothermia

Abstract

Serotonin syndrome can be a rare but life-threatening condition that is commonly the result of a drug-drug interaction causing excessive serotonin activity. The symptoms associated with serotonin syndrome can include hyperthermia, mental status changes, autonomic hyperactivity and neuromuscular abnormalities, all of which can be concealed in the critically ill patient owing to concomitant therapies. The objective of this case report is to describe a probable drug-drug interaction between buspirone and linezolid, and to highlight the potential confounding effects of hypothermia in this case. We present a case of a 28-year-old man who potentially developed serotonin syndrome after coadministration of buspirone and linezolid while being therapeutically cooled for traumatic brain injury. The patient developed hyperthermia, hypertension and tachycardia when buspirone and linezolid were administered concomitantly for 2 days. Symptoms resolved within 24 h after discontinuation of both medications. Caution should be used in patients receiving multiple serotonergic agents in addition to therapeutic hypothermia. The use of therapeutic hypothermia may mask the symptoms associated with serotonin syndrome, thus delaying the diagnosis and treatment of this potentially deadly condition. If a patient requires the combination of such medications, close monitoring for the symptoms of serotonin syndrome is warranted.