The influence of methohexital and propofol on seizure activity and recovery profiles was assessed in a randomized, crossover study involving 13 adult outpatients undergoing electroconvulsive therapy (ECT). Arterial blood pressure, heart rate, hemoglobin oxygen saturation, and electroencephalogram (EEG) activity were monitored during the ECT procedure. After premedication with glycopyrrolate, 0.2 mg intravenously (i.v.), and labetalol 20-30 mg i.v. hypnosis was induced with a bolus injection of either methohexital or propofol, 0.75 mg/kg. Muscle paralysis was achieved by administering succinylcholine, 1.4 mg/kg i.v. Ventilation was assisted using a face mask while administering 100% oxygen. Thereafter, an electrical stimulus was administered and the length of the resulting motor and EEG seizures was measured. Mood level and cognitive function were assessed prior to induction of anesthesia and after ECT. A total of 72 treatment sessions were evaluated. Each patient underwent a minimum of four treatments and received both induction drugs equally. Although the use of propofol was associated with significantly shorter motor and EEG seizure durations (mean +/- SEM) compared with methohexital (34 +/- 1.6 s and 52 +/- 2.9 s vs 39 +/- 1.5 s and 61 +/- 3.0 s, respectively), this difference was not clinically significant because the durations exceeded 30 s in both groups. Although awakening times were similar, both hemodynamic stability and cognitive recovery were more favorable after propofol. Compared with methohexital, the use of propofol was associated with a clinically insignificant decrease in seizure duration. However, propofol was associated with improved hemodynamic stability and an earlier return of cognitive function after ECT.