Actions of a mixture of amphetamine and a barbiturate in man.

The effects in man of a mixture of amphetamine and a barbiturate (15 mg of amphetamine sulphate and 300 mg of cyclobarbitone) and of each of the constituents separately were assessed on the performance of simple mental and motor tasks, on the pulse rate and on subjective reports. The mixture produced a pattern of effects which was different from that produced by either drug separately. It impaired the efficiency of the performance of tasks much less than did the barbiturate drug alone; it produced almost as big a rise in the pulse rate as did amphetamine alone; and it produced reports of feeling "elated" from many more subjects than did either drug separately, though there was no corresponding increase in reports of other feelings and sensations.