Pharmacopsychological investigations concerning the combined effects of dipotassium clorazepate and ethanol.

The effect of a single dosage of 20 mg dipotassium clorazepate (DPC) on reaction times, with and without administration of ethanol (1 g/kg body weight), was studied in 14 male subjects. When administered in the evening, the sort-term effect of DPC consisted of slightly increased optic reaction times and decreased endurance and concentration. With simultaneous administration of ethanol, all types of performance studied were significantly impaired; impairment was more pronounced than with the ethanol tests. On the following morning at the second retest, performance levels almost completely returned to those at the onset of testing. This restitution, however, was not as pronounced with subjects who had only received DPC.