The duration of alcohol intoxication depends on the quantity of alcohol that a person consumes.

An estimated 84% of adults in the United States ages 18 years and older have consumed alcohol.

Engaging in certain activities under the influence of alcohol, such as driving a car, can lead to hazardous outcomes. Before a person consumes alcohol, it is important to know how long they will be impaired.

This article examines the effects of alcohol, their duration, and whether individuals can hasten the sobering process.

Slightly blurred image of a hand holding a glass bottleShare on Pinterest
Marcel/Stocksy United

After being absorbed in the gastrointestinal tract, alcohol enters the bloodstream, where it travels to all the organs. It can take anywhere from 15–45 minutes for a person to feel the full effects of an alcoholic drink.

The liver works to neutralize alcohol. Since it can only metabolize a small amount of alcohol at a time, the rest circulates throughout the body, affecting the central nervous system (CNS) by interfering with the firing of nerve impulses.

This causes intoxication symptoms, such as:

  • cognitive dysfunction
  • reduced coordination
  • sedation

The amount of alcohol in a person’s bloodstream is their blood alcohol content (BAC).

There are six stages of alcohol intoxication based on a person’s BAC:

StageBACSigns
reduced awareness, information processing, and visual acuity0.01– 0.12• being more self-confident or daring
• having a shortened attention span
• being unpredictable, impulsive, and careless
reduced muscle coordination0.09– 0.25• difficulty understanding or remembering things
• not reacting to situations as quickly
• small and large muscle coordination loss
• blurry vision
confusion0.18–0.30• someone not knowing where they are or what they are saying
• dizziness
• being highly emotional — aggressive, withdrawn, or overly happy
• slurred speech
• uncoordinated movements
stupor0.25–0.49• not responding to stimuli
• not able to stand or walk
• vomiting
• lapsing in and out of consciousness
coma0.35–0.50• unconsciousness
• lower-than-usual body temperature
• slower and more shallow breathing
• slower heart rate
• death is also possible
death0.50+• the person’s autonomic nervous system shuts down, resulting in death

It is important to note that in most U.S. states, a BAC of 0.08 is considered legally drunk.

Learn more about how alcohol affects health.

It takes about 1 hour for the average adult to process one unit of alcohol, which is 10 milliliters (ml) or 8 grams.

The alcohol by volume (ABV) also affects a person’s inebriation duration. ABV is the percentage of pure alcohol within a drink’s total liquid volume.

It is possible to calculate the number of units from ABV using the following formula: strength (ABV) x volume (ml) ÷ 1,000 = units.

For example, a person who drinks 355 ml of 6.9% alcohol would be affected by that drink for almost 2.5 hours: 6.9 x 355 ÷ 1,000 = 2.45 units.

The quantity of alcohol a person drinks determines the duration of their intoxication.

Factors that affect the way they may feel include:

  • acquired alcohol tolerance
  • overall health and fitness
  • body size
  • age
  • biological sex
  • drinking speed
  • whether they have eaten and how much
  • the presence of medications or other drugs in their bloodstream

As a result, the same amount of alcohol may affect each person differently.

To become sober, a person needs to stop drinking alcohol and allow enough time for the liver to finish detoxifying the alcohol already in the body.

Some people might believe it is possible to quicken the sobering process with strategies such as drinking coffee and taking cold showers. However, this does not change a person’s BAC, even though it may help them feel temporarily more alert.

Learn more about becoming sober.

The following are some questions people often ask about drinking alcohol.

How long after drinking is it safe to drive?

The time a person should wait after drinking before they drive depends on the amount of alcohol they have consumed.

For example, if a person has one 3-unit (30ml) alcoholic beverage, they should wait at least 3 hours before driving. If they have a second drink, their wait time doubles to 6 hours.

Ideally, a person should not drive after consuming alcohol until it is completely out of their system.

Is it OK to let a drunk person sleep?

Depending on a person’s BAC, it may not be safe to let them sleep unsupervised.

Alcohol can interfere with protective measures such as a person’s gag reflex. A high BAC can increase the risk of asphyxiation if a person vomits and does not have enough intact reflexes to clear their own airway.

The liver detoxifies alcohol from the body but can only do so in small quantities. If a person’s consumption exceeds their rate of alcohol metabolism, intoxication results.

Alcohol intoxication can affect each person differently. Factors influencing how a person feels include their general health, body size, how quickly they drink, and whether they have eaten food.

The duration of intoxication depends on how much alcohol an individual consumes. Typically, it can take at least several hours for their BAC to reduce enough for it to be safe to drive.