Acute and subacute effects of diazepam on psychomotor skills: interaction with alcohol.
Effects of diazepam and alcohol on psychomotor skills were measured in two trials. In the first one, 200 healthy students volunteered for a double-blind single-dose study. Three doses of diazepam (5, 10 and 20 mg) and alcohol (0.5, 0.8 and 1.2 g/kg) were used alone and combined to construct dose-response graphs. All doses of alcohol impaired divided attention while co-ordinative skills were impaired by the 1.2 g/kg dose. Diazepam alone did not impair reactive or co-ordinative skills whereas the combinations of diazepam and alcohol did so. To further elucidate the subactue effects, a double-blind randomized study was conducted administering 2 and 10 mg of diazepam t.i.d. for two weeks to 18 healthy volunteers. The psychomotor tests were performed on the 7th and 14th days of drug administration, and 0.5 g/kg of alcohol was given on either day. Diazepam 2 mg, alone or with alcohol, did not differ from placebo. 10 mg of diazepam slightly increased reaction times but not reaction mistakes, and impaired both co-ordination and attention. Alcohol did not enhance diazepam effects. We suggest that a development of tolerance to diazepam may compensate the deleterious interaction of the agents found in acute studies.
D000328:Adult; D001288:Attention / Q000187:drug effects; D002986:Clinical Trials as Topic; D003975:Diazepam / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004347:Drug Interactions; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D005425:Flicker Fusion / Q000187:drug effects; D006801:Humans; D008297:Male; D009048:Motor Skills / Q000187:drug effects*; D011897:Random Allocation; D011930:Reaction Time / Q000187:drug effects
D000431:Ethanol; D003975:Diazepam