[The cognitive effect of alprazolam in healthy volunteers].

Randomised, double blind placebo controlled crossover study has been performed to evaluate the effect of single dose of anxiolytic alprazolam on the cognitive function in 18 healthy male volunteers. The subject received a single dose of 0.75 mg, 1.75 mg alprazolam or placebo in randomised order. Performances on cognitive tests (immediate and delayed word recall test, digit symbol substitution test, critical fusion frequency and multiple choice reaction test) and subjective rating of the drug effect have been evaluated before and at several occasions after the administration of alprazolam or placebo. According to the results of the statistical analysis alprazolam impaired the performance in cognitive tests dose dependently and induced subjective sedation. The applied test battery proved to be capable to measure the effect of the drugs on the cognitive function in pharmacodynamic studies.