Day-time residual effects and motor activity after three benzodiazepine hypnotics

The benzodiazepine hypnotics triazolam (T) (0.25, 0.5 and 1.0 mg), nitrazepam (N) (10 mg) and flunitrazepam (F) (2.0 mg) were investigated with respect to night-time effects and day-time residual effects, in healthy, young subjects. Drug or placebo was taken orally at home before bed-time. Tests for residual drug effects were administered in the laboratory throughout the following day. They included multiple sleep latency tests, the digit cancellation test, questionnaires, self-ratings and experimenter ratings. In addition, motor activity was recorded with a wrist-worn activity monitor during the drug-night, the day following drug intake, and the two subsequent nights. Residual effects consisted of reduced day-time motor activity (T 0.5, F 2.0), enhanced self-rated day-time sleepiness (T 1.0, F 2.0), increased experimenter-rated tiredness (T 0.5, F 2.0), and impaired performance in the digit cancellation test (F 2.0). Grogginess was a common symptom in the morning after flunitrazepam. All drugs reduced motor activity during sleep, and increased subjective depth and quietness of sleep. Increased motor activity in the second post-drug night was observed after triazolam 0.5 mg. The results indicate that a small dose of a short-acting benzodiazepine may be appropriate for promoting sleep without subsequent day-time residual sequelae.