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

Eur J Clin Pharmacol. 1990;39(1):21-8. doi: 10.1007/BF02657051.


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 self-reports 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.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Adult
  • Affect
  • Alprazolam / adverse effects
  • Alprazolam / blood
  • Alprazolam / pharmacology*
  • Anxiety / psychology
  • Autonomic Nervous System / drug effects*
  • Cognition / drug effects*
  • Diazepam / adverse effects
  • Diazepam / blood
  • Diazepam / pharmacology*
  • Drug Interactions
  • Ethanol / adverse effects
  • Ethanol / blood
  • Ethanol / pharmacology*
  • Female
  • Humans
  • Nordazepam / blood
  • Norepinephrine / blood
  • Psychomotor Performance / drug effects*


  • Ethanol
  • Nordazepam
  • Diazepam
  • Norepinephrine
  • Alprazolam