Having a nightcap or two, or spending a night on the town, might help you fall asleep more quickly, but after that alcohol often messes with your sleep quality.
More accurately, a study of 500 people who drank before going to bed showed that just a nightcap or so would actually facilitate the first part of one’s sleep but usually not interfere with rapid eye movement (REM) sleep, which is the part that settles one emotionally from the previous day’s travails. But a night on the town did indeed prevent REM rejuvenation.
The study also found that the heavier drinkers would often awake during the night and have a hard time returning to sleep, and if they did get into the REM phase of sleep, the dreams would often turn into nightmares rather than emotional/mental reconciliations. Heavy alcohol consumption was even worse for women than men.
Women were found to toss and turn more frequently than men and find it harder to get back to sleep after waking up. This is because women evidently metabolize alcohol more quickly than men, so they get past the sedative phase more quickly and move into the more disruptive phase faster than their male counterparts.
Of course, consuming such large quantities of liquids will also mean more frequent trips to the bathroom, which is obviously sleep disruptive. Alcohol consumption can also trigger acid reflux, again causing sleep difficulties.
Worse, alcohol can turn deadly if mixed with prescription sleep aids such as Lunesta or Ambien. “Somebody could essentially stop breathing if they mix alcohol with any of those medications,” says Dr. Reena Mehra, a sleep-disorder specialist at the Cleveland Clinic.
Finally, alcohol makes snoring in general and the symptoms of obstructive sleep apnea (OSA) in particular even worse since alcohol reduces the muscle tone in the upper airway. Dr. Mehra explains that since alcohol makes the airways essentially collapsible, people suffering from sleep apnea tend stop breathing more frequently and for longer periods after drinking.
Bottom line is to drink in moderation or not at all since alcohol tends to disrupt your sleep in many ways, whether or not you have pre-existing problems.