Midazolam: sleep and performance studies in middle age.

Effects of 10, 20 and 30 mg midazolam on sleep and on performance the next day were studied in six healthy adult males aged between 47 and 53 years. The study was double-blind, placebo-controlled and included another rapidly eliminated benzodiazepine (brotizolam, 0.25 mg) as an active control. With 10 mg midazolam, sleep-onset latency was quicker, and the duration and percentage of stage 2 sleep was increased over the first 6 h. Effects of 20 and 30 mg midazolam were similar to each other. Sleep onsets were earlier, total sleep times and stage 2 sleep were increased, and the sleep efficiency indices improved. During the first 6 h there was reduced duration and percentage of drowsy (stage 1) sleep. There was no consistent evidence of delay to the first period of rapid eye movement sleep, but over the dose range the duration was reduced during the first 2 h. Digit symbol substitution did not show any residual decrement 9 h after ingestion of 10, 20 or 30 mg midazolam. Midazolam may prove to be a particularly useful hypnotic for shiftworkers whose rest periods tend to be shorter than in those who have a regular nocturnal sleep pattern.