What is alcohol intolerance?
Alcohol intolerance is an inherited metabolic disorder. Metabolic disorders affect your metabolism, the way your body converts and uses energy.
An inherited metabolic disorder means you got this condition from your parents — they each passed down a mutated (changed) gene that resulted in this disorder. Even if your parents don’t have the condition, they can pass it to you.
Our bodies are full of enzymes, proteins that help break down food. Alcohol intolerance is a problem with the specific enzyme that helps your body metabolize alcohol. Even drinking a small amount of alcohol (ethanol) causes unpleasant symptoms. Your face may turn pink or red (alcohol flush) and feel warm.
How common is alcohol intolerance?
One study of 948 individuals found that 7.2% self-reported wine intolerance. It happened to the women more than men (8.9% verses 5.2%). It is unclear if that number reflects the general population.
Is alcohol intolerance the same as an alcohol allergy?
People often confuse alcohol intolerance and alcohol allergy, but they aren’t the same condition.
Alcohol intolerance is a genetic, metabolic disorder of the digestive system. Your body doesn’t process alcohol the way it should.
Alcohol allergy is an immune system response — your immune system overreacts to an ingredient in alcohol. You may be allergic to one of the substances in alcohol (a chemical, grain or preservative, such as sulfite).
The symptoms differ slightly. Both alcohol intolerance and an allergy can cause nausea. But the hallmark symptom of alcohol intolerance is flushing of the skin of the chest, neck and face.
Symptoms of an alcohol allergy include rashes, itchiness, swelling and severe stomach cramps. Allergy symptoms are often more painful and uncomfortable than alcohol intolerance symptoms. In rare cases, if untreated, an alcohol allergy can be life-threatening.
If you have any unpleasant symptoms after drinking alcohol, see your healthcare provider. Your provider can help get to the bottom of your symptoms and recommend the best next steps.
Is alcohol intolerance the same as being intoxicated?
No, alcohol intolerance is not the same as being intoxicated or drunk. Alcohol intolerance doesn’t mean you become drunk faster or after drinking less alcohol. And the condition does not increase your blood alcohol level, either. Often, people with alcohol intolerance drink less, because the symptoms they experience are so unpleasant.
Who might have alcohol intolerance?
People of East Asian descent are more likely to have the inherited genetic mutation that causes alcohol intolerance, so they develop the condition at higher rates. Anyone can have the enzyme problem that causes alcohol intolerance.
What causes alcohol intolerance?
A genetic metabolic disorder causes alcohol intolerance. When most people ingest alcohol, which contains ethanol:
- An enzyme called alcohol dehydrogenase (ADH) helps metabolize (process) the ethanol.
- Your liver converts the ethanol to acetaldehyde, a substance that can cause cell damage.
- Another enzyme called aldehyde dehydrogenase 2 (ALDH2) helps convert acetaldehyde to acetic acid (vinegar), which is nontoxic.
In people with alcohol intolerance, a genetic mutation (change) makes ALDH2 less active or inactive. As a result, your body can’t convert acetaldehyde to acetic acid. Acetaldehyde starts to build up in your blood and tissues, causing symptoms.
What are symptoms of alcohol intolerance?
Alcohol flushing syndrome is a major sign of alcohol intolerance. Your face, neck and chest become warm and pink or red right after you drink alcohol.
Other symptoms include:
- Nausea and vomiting.
- Rapid heartbeat (tachycardia) or heart palpitations.
- Hypotension (low blood pressure).
- Throbbing headache, fatigue and other hangover-like symptoms.
- Stuffy nose.
- Worsening asthma.