Serotonin Syndrome Precipitated by the Use of Cocaine and Fentanyl.

Serotonin syndrome (SS) is a condition that occurs following the administration of serotonergic drugs. The syndrome is classically associated with the simultaneous administration of two serotonergic agents. Herein, we present a unique case of SS precipitated by cocaine and fentanyl in conjunction with previously prescribed oxycodone/paracetamol, trazodone, and mirtazapine. The patient was brought to the hospital with chief complaints of altered mental status, abdominal pain, nausea, and vomiting. The patient used her friend's fentanyl patch, and her urine drug screen was positive for cocaine. She was intubated and admitted to the intensive care unit for a low Glasgow Coma Scale score of 6 and autonomic instability. All the inciting agents were stopped, supportive treatment was given, and the patient was sedated with benzodiazepines and propofol. She received cyproheptadine, and the patient was extubated and clinically improved over the next 24 hours. Cocaine and fentanyl are not classically associated with SS. We did not encounter any cases where SS was precipitated by the combined use of cocaine and fentanyl in patients taking psychotropic medications during our literature review. This case report underlines the association of SS with cocaine and fentanyl. SS should be suspected in patients using cocaine and fentanyl or any other substance of abuse along with psychotropic agents.