What Causes A Sudden Change In Alcohol Tolerance?

Medically Reviewed by Johnelle Smith, M.D. on July 28, 2023

Alcohol tolerance can change suddenly according to a variety of factors. These factors can be psychological, environmental, or physiological. You can also develop an alcohol intolerance due to largely biological reasons.

What Causes A Sudden Change In Alcohol Tolerance?

Drinking alcohol over the course of years or months can cause moderate or heavy drinkers to experience sudden changes to their tolerance.

Sometimes, they can experience the sudden onset of alcohol intolerance as well. In either case, there are a variety of factors that could influence these sudden changes.

Factors That May Cause A Change In Alcohol Tolerance

There are a number of factors that cause sudden changes in how you experience the effects of alcohol. These include environmental, social, learned, and ethnic factors, but there are others.

Alcohol Consumption

Your history of alcohol consumption can have an effect on your alcohol tolerance.

For example, if you frequently drink the same number of alcoholic beverages over a period of time, you may develop a functional tolerance to alcohol. This is true even if you drink small amounts of alcohol.

In other words, your body builds a level of tolerance to the amount of alcohol that you repeatedly consume, so you don’t feel its effects as intensely as you did when you started.

Alcohol Metabolism

The efficiency with which your body metabolizes alcohol can change. For instance, exercise can affect your alcohol tolerance because it may reduce fat, increase body mass, and increase your metabolism.

Alcohol Allergy

It is possible to develop worsening symptoms because of an alcohol allergy.

It is important to make a distinction between an allergic reaction to some of the components of alcoholic beverages and a true alcohol allergy.

You may develop an allergy to some of the ingredients in alcoholic beverages that cause you to develop an alcohol intolerance.

Common allergens in alcoholic drinks include:

  • grapes
  • rye
  • wheat
  • hops

True alcohol allergies are rare and can cause severe symptoms, such as:

  • swelling
  • hives
  • vomiting
  • loss of consciousness
  • anaphylaxis

Aldehyde Dehydrogenase Enzyme

The aldehyde dehydrogenase (ALDH) enzyme is key to metabolizing alcohol. The liver first uses alcohol dehydrogenase (ADH) to break down ethanol into acetaldehyde.

Then ALDH breaks acetaldehyde down into acetic acid, which, unlike ethanol, is non-toxic.

If your body produces a lot of ALDH, you could have a higher tolerance to alcohol as long as your production of ALDH is greater than the influx of acetaldehyde.

You could also have an alcohol intolerance if you have an inherited lack of an ALDH variant called ALDH2. The lack of this variant is common in people of Asian descent.


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Why The Body May Start To Reject Alcohol

Just as there are many reasons why your body may develop a tolerance for alcohol, there are just as many reasons why you may develop an alcohol sensitivity or alcohol intolerance.

Immune System Response

Your immune system may be triggered to release histamine during an allergic reaction. This could complicate the fact that histamines are often found in beer and wine.

The resulting build-up could trigger migraines.

Allergic Reaction

You could have either an allergy to ingredients in an alcoholic drink, such as beer or wine, or you could have a true allergy to alcohol.

Both allergies can be developed over time, and their onset could be sudden.

Health Conditions

Health conditions can also affect your ability to tolerate alcohol if you have asthma or common allergies. Hodgkin’s lymphoma is a rare and severe health condition that causes your body to reject alcohol.

How To Know If You’ve Developed An Alcohol Intolerance

The symptoms of an alcohol allergy can be quite different from the symptoms related to alcohol intolerance.

The symptoms of alcohol intolerance include:

  • increased heart rate
  • low blood pressure
  • hives
  • nasal congestion
  • red face
  • nausea and vomiting

True alcohol intolerance is a genetic trait that is commonly found among people of Asian descent. A reaction to ingredients in alcoholic beverages may develop over time.

Treatment Options For Alcohol Use Disorder

An alcohol intolerance may be a blessing in disguise because greater tolerance for alcohol can lead to an alcohol use disorder (AUD), causing you drink more and more to achieve the same effect.

Fortunately, alcohol addiction treatment is available, and it is entirely possible that you have a treatment center in your town.

Alcohol rehab programs can address different types of alcohol use disorder, such as binge drinking or heavy drinking, as well as the effects of alcohol and co-occurring mental health issues.

Inpatient rehab programs offer comprehensive recovery services alongside healthcare to ensure the best treatment outcomes.

Find A Substance Use Treatment Program Near You

At AddictionResource.net, we believe that you or your loved one should receive confidential and effective help in beginning your journey to sobriety. Call us today for more information.

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Medically Reviewed by
Johnelle Smith, M.D. on July 28, 2023


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