Midazolam and triazolam: hypnotic action and residual effects after a single bedtime dose.

The hypnotic action and residual effects of a single bedtime dose of 8-chloro-6(2-fluorophenyl)-1-methyl-4H-imidazo[1,5-a][1,4]benzodiazepine (midazolam, Ro 21-3981, Dormicum) (7.5 or 15 mg) or 8-chloro-6(o-chlorophenyl)-1-methyl-4H-S-triazolo[4,3-a] [1,4]benzodiazepine (triazolam) (0.25 or 0.5 mg) were investigated in young, healthy adults. Motor activity was continuously recorded by a wrist-worn activity monitor. In comparison to placebo, all compounds reduced night-time motor activity in the first half, but not in the second half of the night. Subjects rated their sleep as more quiet. Neither the spontaneous daytime motor activity nor the self-rated state in the morning and at noon was affected by drug intake in the preceding night. Performance in the morning as measured by a psychomotor test was significantly impaired only after triazolam 0.5 mg. There was no evidence for rebound insomnia in the 3 nights following drug intake. The results indicate that midazolam 15 mg and triazolam 0.25 mg have a reliable hypnotic action without significant residual sequelae.