Alcohol and sleep I: effects on normal sleep - PubMed

This qualitative review evaluates the scientific evidence regarding alcohol's impact on nocturnal sleep in healthy volunteers. Findings indicate that while alcohol reduces sleep onset latency at all dosages, it consistently disrupts sleep quality in the second half of the night. High doses specifically decrease total REM sleep and delay the first REM period, whereas an increase in slow wave sleep during the first half of the night is a robust effect across all demographics. Ultimately, the apparent sedative benefit of alcohol is offset by significant fragmentation of sleep architecture.