Heroin and human sleep

Abstract

It has been suggested that drugs of addiction, e.g. barbiturates, cause suppression of REM sleep followed by immediate withdrawal rebound. In rats it has been demonstrated that morphine will suppress REM sleep and, in a pilot study of withdrawal in humans, there was a delayed REM sleep rebound. 1. A: Four normal male volunteers had a subcutaneous injection of 7.5 mg heroin on 3 successive nights. During this period the percentage of REM sleep was decreased with respect to baseline values for these subjects and showed a trend back to control values over the 3 nights. On withdrawal there was a moderate but immediate percentage of REM sleep increase which, over the first 3 h of sleep, was significant. 2. B: Two of the subjects from A received a further 7 injections of 7.5 mg heroin some 2 months after the previous ones. Again the proportion of REM sleep was reduced in both subjects and there was the trend back to baseline values over the 7 nights. One subjects had increased REM sleep immediately on withdrawal. Evidence of withdrawal was apparent for some 2 months after stopping heroin. Other evidence of withdrawal was seen in the decreased delay to the first REM period (< 45 min) and in the increased amount of REM sleep in thefirst 2 h of sleep (> 35 min). The other subject showed little evidence of withdrawal effects in sleep though there was a short delay to the first REM period on nights 4 and 11 of withdrawal. His proportion of REM sleep was never significantly above baseline values, indicating that there can be considerable individual differences in the effects of withdrawal of heroin. In both experiments it was noted that, far from giving an undisturbed sleep, heroin administration resulted in an increased frequency of shifts to stage 1 sleep (drowsiness) or wakefulness and an increased delay to the onset of the first stage 2 of the night.