DL‐α‐Methyltryptamine methyl sulfate in oral doses of 20 mg. and DL‐α‐ethyltryptamine acetate in oral doses of 150 mg. were compared objectively and subjectively in a group of trained, normal human volunteers. Blood pressure, pulse rate, pupil diameter, oral temperature, and grip strength were recorded hourly. Subjective effects were recorded 3 and 24 hours after administration of the drugs. A significant decrease in heart rate occurred 2 hours after α‐ethyltryptamine. Significant rises in systolic and diastolic blood pressure occurred 3 hours after α‐methyltryptamine. There also were significant increases in pupil diameter after each drug. The subjective effects were similar in many respects, but there were important differences. The onset of action was rapid for α‐ethyltryptamine and slow for α‐methyltryptamine; duration of action was longer for the latter than for the former. The most common effect, reported by 8 of the 11 subjects taking α‐ethyltryptamine, was a feeling of being elated or intoxicated. The most common effects reported by those who took α‐methyltryptamine were nervous tension and restlessness not unlike those produced by 50 to 60 γg of lysergic acid diethylamide.