Alcohol is not a good sleep aid.

Alcohol acts as a sedative in people who drink before bed, as evidenced by the delta frequency electroencephalogram (EEG) activity of Slow Wave Sleep (SWS), but it is later linked to sleep disruption.
‘People are likely to focus on the commonly reported sedative properties of alcohol, which is reflected in shorter times to fall asleep, particularly in adults, rather than the sleep disruption that occurs later in the night,’ said Christian L. Nicholas of Australia’s University of Melbourne.

The researchers gathered 24 healthy 18- to 21-year-old social drinkers who had consumed less than seven standard drinks per week in the previous 30 days for the study.
Pre-sleep alcohol and a placebo were given to each participant, followed by standard polysomnography (a multi-parametric test used in the study of sleep) with comprehensive EEG recordings.
The results showed that alcohol increased frontal alpha power significantly.

The take-home message here is that, despite appearing to help you fall asleep faster, alcohol is not a particularly effective sleep aid. In fact, the quality of your sleep is significantly impacted and disrupted,’ Nicholas explained.
The study will be published in the journal Alcoholism: Clinical & Experimental Research in the near future.