A Case of Serotonin Syndrome Induced by Dextromethorphan in a Patient on Antidepressants, as Suspected by a Pharmacist

Abstract

Serotonin syndrome refers to the adverse events caused by serotonin-based drugs such as antidepressants. Its clinical manifestations include psychiatric and neurovegetative symptoms. In this communication, we report our experience with an 83-year-old woman receiving antidepressants, who developed subjective symptoms such as heavy sweating, dizziness, and tremor after starting treatment with dextromethorphan. Treatment with antidepressants was continued, but five months later, the patient experienced symptoms of heavy sweating, elevated blood pressure, tremor, and anxiety. In her case, serotonin syndrome was suspected by a pharmacist working in a pharmacy, who promptly carried out early intervention and assisted in the prevention of recurrence. In elderly patients who are prescribed dextromethorphan and antidepressants, the possibility of occurrence of serotonin syndrome needs to be taken into consideration in the follow-up of the clinical course.