EFFECTS OF SINGLE DOSES OF ALPRAZOLAM AND DIAZEPAM, ALONE AND IN COMBINATION WITH ETHANOL, ON PSYCHOMOTOR AND COGNITIVE PERFORMANCE AND ON AUTONOMIC NERVOUS-SYSTEM REACTIVITY IN HEALTHY-VOLUNTEERS

Effects of alprazolam, alone and in combination with ethanol, on psychomotor and cognitive performance were studied in healthy male volunteers and compared to effects of diazepam. Alprazolam 2 mg produced relatively long-lasting impairments on tests of tracking, verbal and nonverbal information processing, and memory, and decreased blood pressure without a change in heart rate or plasma norepinephrine levels. Although ethanol consumption was demonstrated to produce additive decrements in performance on certain tasks, there was little evidence to support a synergistic effect. Alprazolam 2 mg was accompanied by increased selfreports of side effects, especially drowsiness. Low dose alprazolam, diazepam, and ethanol produced significantly fewer side effects than 2 mg alprazolam, but significantly more than placebo. © 1990 Springer-Verlag.