Comparative amnestic effects of benzodiazepine hypnotic agents.

The effects of triazolam 0.5 mg and temazepam 30 mg on immediate and delayed recall in normal and insomniac subjects were evaluated in three separate, randomized, placebo-controlled, parallel group studies. Neither drug caused significant impairment of immediate recall. In the tests of delayed recall, triazolam caused a consistent anterograde amnestic effect. No significant impairment of delayed recall was observed in the temazepam study. Anterograde amnesia is thought to be a dose-related effect of benzodiazepines. Compounds with high benzodiazepine receptor affinity such as triazolam are thought to cause this type of amnesia more often than the lower-affinity compounds such as temazepam.