Alcohol and Sleep

Alcohol Consumption Can Induce Sleep Disorders

Woman Trying to Sleep
Alcohol Causes Sleep Disturbances. © Getty Images

Alcohol consumption at almost any level can cause sleep disturbance and induce sleep disorders. Drinking alcohol can disrupt the structure and duration of sleep states, alter total sleep time, and affect the time required to fall asleep.

We don't fully understand why the body requires sleep, but we do know that lack of sleep is linked to serious problems including increased risk of depressive disorders, heart disease, and other health problems.

We also know that excessive daytime sleepiness, resulting from a lack of sleep, is linked to impaired social and occupational function, memory deficits, and risk of having a vehicle crash.

We all need a certain amount of sleep, but alcohol consumption can:

  • Disturb normal sleep patterns
  • Produce potential health consequences from disturbed sleep
  • Increase daytime sleepiness and performance

Of course, not being able to sleep is a relapse risk for recovering alcoholics.

What Is a Normal Sleep Pattern?

Normal sleep consists of two alternating states of sleep in which brain waves exhibit different types of activity:

Additionally, research has identified a transitional light sleep stage that occurs at intervals during the sleep period.

During slow-wave sleep, the brain waves are very slow. It is deep, restful sleep and usually makes up about 75 percent of a night's sleep.

Rapid eye movement sleep occurs periodically during sleep time and makes up about 25 percent of sleep time for young adults. Episodes of REM sleep can recur about 90 minutes and last from 5-30 minutes at a time.

REM sleep, during which the eyes exhibit rapid movements while the person is still sleeping, is less restful and is usually associated with dreaming.

Science does not know what function REM sleep performs for the body, but it seems to be required for restoration. Some studies have found that when laboratory rats are deprived of REM sleep it can result in death within a few weeks.

How Does the Brain Control Sleep?

It was originally thought that sleep was the result of decreased activity in the brain's systems that maintained wakefulness, but research has shown that sleep is an active process of the brain, controlled by nerve centers in the lower brain stem.

Some of these nerve stems produce serotonin, a chemical which has been linked to the onset of sleep and with the regulation of slow wave sleep. Other nerve cells produce norepinephrine, which has been found to regulate REM sleep and facilitate arousal.

It is not known exactly how these and other chemicals in the brain interact to control sleep, but we do know that alcohol consumption alters the function of these chemical messengers and therefore alters sleep patterns.

Alcohol and Sleep in Those Without Alcoholism

Many people suffering from insomnia will take a drink before bedtime to help them fall asleep.

After an initial stimulating effect, alcohol's sedating effects can reduce the time required to fall asleep.

But, alcohol's effects do not end there. Research shows that alcohol consumed within an hour of bedtime will disrupt sleep in the second half of the sleep period, causing the person to sleep fitfully - awakening from dreams and not being able to get back to sleep easily.

Over time, the drink before bedtime works even less effectively. With continued consumption, studies found, alcohol's sleep-inducing effects decrease, while its sleep disturbance effects increase.

This is particularly true for elderly adults  because drinking produces higher levels of alcohol in their blood and brain compared to younger drinkers. Consequently, older adults who take a drink before bedtime can experience an increased risk for falls and injuries if they get up and walk during the night.

'Happy Hour' Drinks Can Affect Sleep Too

Studies have found that alcohol consumed even six hours before bedtime can increase wakefulness during the second half of sleep, even though the alcohol consumed has already been eliminated from the body.

Researchers believe the alcohol causes a long-lasting change in how the body regulates sleep.

Alcohol and Breathing Disorders

Chronic alcohol use appears to be linked to an increased risk for sleep apnea, especially among drinkers who snore.

Obstructive sleep apnea is a disorder in which the upper air passage narrows or closes during sleep, causing interrupted breathing. When this happens, the person will awaken, resume breathing and then return to sleep.

However, incidents of apnea followed by awakening can occur hundreds of times during the night, significantly reducing sleep time.

Furthermore, drinking moderate to high amounts of alcohol prior to sleep can narrow the air passage, causing episodes of apnea in persons who normally do not exhibit sleep apnea symptoms.

Why is this effect of alcohol on apnea important? Sleep apnea sufferers who drink two or more drinks a day are five times more likely to be involved in a fatigue-related traffic crash than those who do not drink.

Additionally, research has linked the combination of sleep apnea, snoring, and alcohol consumption with an increased risk of heart attack, arrhythmia, stroke, and sudden death.

Aging, Alcohol and Sleep Disturbance

When people get older they naturally experience a decrease in slow wave sleep and increase in nighttime wakefulness. Studies have found that people over 65 often awake 20 times or more during the night.

This leads to sleep that is less restful and restorative and can encourage the use of alcohol to try to increase sleep. The results, however, is an increase in alcohol-related sleep disturbances for older adults.

Alcoholic Drinking, Withdrawal, and Sleep

For those with severe alcohol use disorders, sleep disturbances included a longer time required to fall asleep, frequent awakenings, a decrease in quality sleep, and daytime fatigue.

It seems reasonable to think that alcoholics who quit drinking would return to normal sleep patterns, but actually, the sudden cessation of alcohol consumption can result in alcohol withdrawal syndrome, which can produce pronounced insomnia and persistent sleep fragmentation.

Lack of sleep is one of the most common symptoms mentioned by those who are going through alcohol withdrawal after they stop drinking.

Alcoholics going through withdrawal can experience:

  • Reduction in restful sleep
  • Increased REM sleep related to withdrawal hallucinations
  • Sleep consisting of brief periods of REM sleep
  • Sleep interrupted by numerous awakenings

Recovery, Sleep and Relapse

After the withdrawal symptoms subside, alcoholics can experience some improvement in sleep patterns, but for some alcoholics normal sleep patterns may never return, even after years of sobriety.

Studies have found that recovering alcoholics tend to sleep poorly, have less slow wave sleep, and increased wakefulness, resulting in less restorative sleep and daytime fatigue.

Ironically, if the recovering alcohol returns to heavy drinking, their slow-wave sleep will increase and their nighttime wakefulness will decrease, at least initially. This mistaken impression that alcohol consumption improves sleep is a major reason that many alcoholics relapse. The relief they get, however, is only temporary.

As they continue to drink, their sleep patterns soon become disrupted again. The idea that alcohol consumption improves sleep is, in reality, only a myth.


National Institute on Alcohol Abuse and Alcoholism. "Alcohol and Sleep." Alcohol Alert July 1998

Continue Reading