Transient Syncope and ECG Changes Associated With the Concurrent Administration of Clozapine and Diazepam

Letter to the Editor

Sir: Syncopal attacks have been reported in patients who were treated with a combination of clozapine and benzodiazepines. These patients had a sudden loss of consciousness and no visible respiration or measurable blood pressure followed by recovery within 5 minutes to a few hours. Also, a lethal case and severe orthostatic hypotension4 have been reported for this combination of drugs. We describe a patient who developed a brief syncopal attack with significant electrocardiogram (ECG) changes after clozapine dosage was increased to 300 mg/day while he was receiving diazepam (30 mg/day).