Effect of a metabolite of diazepam, 3-hydroxydiazepam (temazepam), on sleep in man.

The effect of 3-hydroxydiazepam (temazepam, 10 mg and 20 mg) on sleep was studied in six healthy adult males using electroencephalography for sleep measures, and analogue scales for subjective assessments of well-being and sleep quality. The effects were compared with diazepam (5 mg and 10 mg). Effect on total sleep time was restricted to the night of ingestion. There was no change in total sleep time after temazepam (10 mg), but with 20 mg total sleep time was increased (P = 0.01). Sleep onset latencies and awakenings were markedly reduced. Temazepam reduced the duration (min) of stage 0 (P = 0.05) and stage 1 (P = 0.01) sleep, and the effect on stage 1 was seen during each two hourly interval of sleep (P = 0.05). No effects were observed with stage 3, 3+4 and REM sleep, except that the appearance of the first REM period was delayed with temazepam (20 mg) (P = 0.001). The subjects, as a group, reported improved sleep, but subjective assessments of well-being were not altered. Correlations were calculated for sleep measures and subjective assessments.