Sleep laboratory study of the effects of midazolam in insomniac patients

The effects of midazolam, a short-acting imidazobenzodiazepine, on the sleep cycle of insomniac patients were assessed by means of polygraphic recordings. Baseline placebo nights were compared with drug (30 mg p.o.) and placebo withdrawal nights. The compound was effective in inducing and maintaining sleep on short- and intermediate-term administration. Tolerance was not observed following two weeks of drug use. Subjective reports corroborated the effectiveness of midazolam as a hypnotic. In regard to its effects on sleep stages, midazolam markedly decreased Stage 3 and abolished Stage 4 sleep, while Stage 2 was augmented. REM sleep percentage was not significantly affected. Withdrawal of midazolam was followed by rebound insomnia, in which sleep latency, total wake time and wake time after sleep onset were increased above baseline. Side-effects related to midazolam administration included headache, muscular weakness and dizziness. They were mild and wore off 1-2 hours after awakening.