EFFECTS OF DAYTIME ADMINISTRATION OF ZOLPIDEM VERSUS TRIAZOLAM ON MEMORY

To determine whether zolpidem (an imidazopyridine hypnotic) produces a mnestic effects which are similar to those produced by triazolam (a be nzodiazepine hypnotic), 70 subjects were adminstered either triazolam (0.125, 0.25, or 0.5 mg), zolpidem (5, 10 or 15 mg) or placebo, then t ested on Simulated Escape, Restricted Reminding, and Paired-Associates memory tests at 1.5 hours post-dosing (i.e., near the time of estimat ed peak blood concentration for both drugs) and again at 6 hours post- dosing. Triazolam 0.5 mg produced the greatest memory impairment at bo th test times, and also produced the greatest degree of sedation durin g intervening daytime naps in a non-sleep-conducive environment. Other doses of triazolam and zolpidem produced less memory impairment, but also failed to significantly enhance sleep. The results are consistent with the view that the amnestic and hypnotic effects of these sleep-i nducing medications are functionally coupled.