Sleep, sleepiness, sleep disorders and alcohol use and abuse.

The study of ethanol's effects on sleep has a long history dating back to the work of Nathaniel Kleitman. This paper reviews the extensive literature describing ethanol's effects on the sleep of healthy normals and alcoholics and the newer literature that describes its interactive effects on daytime sleepiness, physiological functions during sleep, and sleep disorders. Ethanol initially improves sleep in non-alcoholics at both low and high doses with disturbance in the second half of the night sleep at high doses. Tolerance develops to the initial beneficial effects. In alcoholics sleep is disturbed both while drinking and for months of abstinence and the nature of the abstinent sleep disturbance is predictive of relapse. Ethanol interacts to exacerbate daytime sleepiness and sleep-disordered breathing, even inducing apnea in persons at risk. Ethanol's effects on other physiological functions during sleep and other sleep disorders has yet to be documented. 2001 Harcourt Publishers Ltd