Alcohol intolerance: symptoms, causes, and risk factors

Alcohol intolerance occurs when the body struggles to process alcohol, leading to uncomfortable reactions. This condition is typically due to a genetic enzyme shortage or an inability to metabolize certain substances in alcohol, such as sulfites or histamines.

Signs of alcohol intolerance may involve facial flushing, red and itchy skin patches (hives), worsening of asthma symptoms, nasal congestion or runniness, lowered blood pressure, nausea and vomiting, and diarrhea.

The reasons behind alcohol intolerance include sulfites and other preservatives, certain chemicals, grains or their components, and histamine.

Alcohol intolerance is more likely in individuals of East Asian heritage and those with asthma, allergic rhinitis, Hodgkin’s lymphoma, or grain allergies.

What is alcohol intolerance?

Alcohol intolerance is a metabolic disorder where the body reacts immediately after drinking alcohol because it cannot properly process the substance, unlike alcohol addiction, which involves compulsive and repeated use despite harmful outcomes. This issue often stems from a hereditary deficiency of the enzyme aldehyde dehydrogenase 2 (ALDH2), which is crucial for breaking down acetaldehyde, a toxic byproduct of alcohol.

When enzymatic function is insufficient, acetaldehyde builds up in the blood, producing effects like facial flushing, nausea, and a rapid pulse. Some people also face digestive issues from being unable to tolerate histamines or sulfites in alcoholic drinks, leading to symptoms similar to allergic reactions.

The way the body metabolizes alcohol is central to these responses, as an inability to break down alcohol’s components effectively causes ongoing intolerance symptoms. In contrast to a true allergy that involves the immune system, alcohol intolerance is due to the body's metabolic limitations and usually occurs consistently with each alcohol intake.

How frequently does alcohol intolerance occur?

Alcohol intolerance is significantly more prevalent than genuine alcohol allergy. Data from a 2012 survey by Wigand et al., “Prevalence of Wine Intolerance,” revealed that 7.2% of respondents (68 out of 948) reported being intolerant to wine. Intolerance to beer and other alcoholic drinks was found to be associated with wine intolerance. Women reported wine intolerance at higher rates than men (8.9% compared to 5.2%).

A 2014 publication by Lee et al., “Asian flushing: genetic and sociocultural factors of alcoholism among East Asians,” noted that about 40% of East Asians (including Chinese, Japanese, and Koreans) experience facial flushing, called “Asian flush” or “Asian glow,” after alcohol intake. This response results from distinct genetic differences affecting how alcohol is metabolized.

Specific variants of alcohol dehydrogenase (ADH) enzymes (ADH1B2 and ADH1C1) rapidly convert alcohol into acetaldehyde, but a slow or inactive aldehyde dehydrogenase (ALDH2*2) enzyme hampers the breakdown of acetaldehyde.

In essence, East Asians absorb alcohol quickly in the initial phase but process it more slowly in the subsequent stage, causing unpleasant reactions when drinking. Conversely, true alcohol allergies are uncommon across all groups. While East Asians are more frequently affected, alcohol intolerance can develop in people of any background.

What are the symptoms of alcohol intolerance?

Symptoms of alcohol intolerance point to sensitivity to alcohol and typically emerge soon after consumption, unlike the general effects of alcohol, which vary based on the amount and frequency of intake. The signs of alcohol intolerance include the following.

• Redness on the face (flushing)
• Lumps of red, itching skin (hives)
• Pre-existing asthma worsens
• Runny or stuffy nose
• Low blood pressure
• Vomiting and nausea
• Diarrhea
• Throat irritation or pain
• Cold Sensations (Flu-like Symptoms)
• Jaw pain

1. Redness on the face (flushing)

When acetaldehyde, a harmful byproduct of alcohol metabolism, accumulates in the body, it causes facial blood vessels to dilate. A deficiency in the enzyme aldehyde dehydrogenase 2 (ALDH2) prevents this toxin from breaking down efficiently, leading to heightened sensitivity.

This results in skin flushing, visible redness, and a burning or warm sensation, particularly across the face, neck, or chest. These symptoms typically intensify with greater alcohol consumption, as the buildup of toxins overwhelms the body’s ability to process them.

2. Lumps of red, itching skin (hives)

Hives or red bumps may appear due to histamines and sulfites in alcoholic drinks, which can provoke an immune-like reaction. The body releases histamine, leading to inflamed, itchy skin.

Wine, beer, and other fermented beverages often intensify these symptoms. Hives typically appear shortly after drinking and may last for several hours, often accompanied by facial flushing or throat discomfort, especially in sensitive individuals.

3. Pre-existing asthma worsens

Alcohol can trigger or worsen asthma symptoms in people with the condition. Over 40% of asthmatic individuals report alcohol-induced respiratory symptoms. Wine and beer, in particular, contain histamines and sulfites that may prompt bronchoconstriction—narrowing of the airways.

Symptoms can include coughing, wheezing, and shortness of breath. Those with asthma and alcohol intolerance may also notice throat irritation, as airway inflammation extends to the upper respiratory tract.

4. Runny or stuffy nose

Histamines and other ingredients in alcohol cause nasal passage inflammation and increased mucus production, leading to a runny or congested nose. This symptom may be accompanied by sneezing, postnasal drip, or sinus pressure.

Individuals may also experience a sore or scratchy throat after drinking, particularly with beverages high in histamines. This irritation is often due to nasal drainage combined with local inflammation, making it feel like alcohol makes your throat hurt.

5. Low blood pressure

Drinking alcohol can interfere with the body’s normal blood pressure regulation, especially in individuals with alcohol intolerance. A 2000 study by Narkiewicz et al. found that alcohol can significantly lower blood pressure upon standing, increasing the risk of lightheadedness or fainting.

This drop in blood pressure occurs because alcohol dilates blood vessels and impairs the body’s ability to maintain vascular tone. Dizziness, blurred vision, or fatigue may follow, particularly after drinking even small amounts.

6. Vomiting and nausea

Alcohol intolerance often leads to nausea and vomiting, even after consuming small amounts. This happens because alcohol increases stomach acid and irritates the stomach lining.

Yes, drinking alcohol can hurt your stomach, especially in those with alcohol intolerance. The presence of acetaldehyde and stomach acid can cause burning, cramping, and even gastritis, leading to persistent nausea or vomiting. Frequent episodes can result in dehydration and an imbalance of electrolytes.

7. Diarrhea

Alcohol, particularly when combined with artificial sweeteners or mixers, can disrupt digestion. These additives may irritate the gastrointestinal tract, increasing water content in the intestines and triggering diarrhea.

Individuals with alcohol intolerance may also experience stomach pain, bloating, and urgency after drinking. In some cases, these digestive issues may overlap with acid reflux or throat irritation, further adding to discomfort after alcohol consumption.

8. Throat irritation or pain

While not always listed as a primary symptom, throat pain can occur in individuals with alcohol intolerance. Alcohol can irritate the mucosal lining of the throat, especially if consumed in high concentrations (e.g., spirits or liquors) or in combination with other allergens like histamines.

For some, alcohol creates a burning sensation or soreness in the throat soon after drinking. This symptom is often mistaken for a minor infection, but can be a direct reaction to alcohol-related sensitivity. If you notice that drinking alcohol makes your throat hurt consistently, it may indicate intolerance.

9. Cold Sensations (Flu-like Symptoms)

Some individuals experience chills or a sensation of coldness after consuming alcohol. This reaction may be attributed to alcohol-induced vasodilation, which can lead to a drop in core body temperature, resulting in feelings of cold. Additionally, alcohol can impair the body's thermoregulatory mechanisms, making it more susceptible to temperature fluctuations. While not as prevalent as other symptoms like flushing or nasal congestion, these cold sensations are reported by a subset of individuals with alcohol intolerance.

10. Jaw Pain

Jaw discomfort or pain following alcohol consumption can be linked to temporomandibular disorders (TMD), which affect the jaw joint and surrounding muscles. Alcohol may exacerbate TMD symptoms due to its muscle-relaxant properties, potentially leading to increased joint movement and strain. Studies have indicated that individuals who consume alcohol regularly may have a higher prevalence of TMD symptoms, including jaw pain. For instance, research involving Finnish conscripts found that those consuming alcohol at least once a week reported higher instances of jaw pain compared to less frequent drinkers.

Why do I sneeze when I drink alcohol? 

Sneezing after consuming alcohol is often linked to alcohol intolerance, a condition where the body struggles to metabolize certain components found in alcoholic beverages. This reaction is primarily due to the presence of histamines and sulfites in drinks like wine, beer, and champagne. Histamines, produced during fermentation, can trigger allergy-like symptoms such as sneezing, nasal congestion, and a runny nose, especially in individuals with histamine sensitivity or intolerance. Sulfites, commonly used as preservatives, may also provoke respiratory reactions in sensitive individuals.

Additionally, alcohol can cause vasodilation, leading to swelling of the nasal passages and further contributing to nasal congestion and sneezing. For those with alcohol intolerance, these symptoms can occur even with minimal alcohol intake. It's important to note that such reactions are not due to a true allergy to alcohol itself but rather to the body's inability to process certain substances within alcoholic drinks.

If you consistently experience sneezing or other adverse symptoms after drinking alcohol, it may be advisable to consult a healthcare professional to determine the underlying cause and discuss potential management strategies.

How long do alcohol intolerance effects typically persist?

Alcohol intolerance symptoms may persist anywhere from half an hour to several hours. Facial flushing usually subsides within minutes, while stronger reactions such as severe headaches or nausea can continue for one to two hours or even longer after alcohol is consumed.

Sometimes, aftereffects like alcohol-induced nausea, tiredness, or mild digestive upset can last up to a day, particularly when larger amounts are consumed. Symptom duration differs for each person and is affected by various factors, and it’s important not to confuse these reactions with alcohol withdrawal, which occurs when alcohol is stopped after long-term use.

How much alcohol is consumed and the body’s efficiency in metabolizing it both play key roles in determining how long symptoms last.

Why are some people completely resistant to alcohol intolerance?  

Some people appear completely resistant to alcohol intolerance due to a combination of genetic, metabolic, and neurobiological factors that influence how their bodies process alcohol. Genetically, individuals with fully functional variants of the ALDH2 (aldehyde dehydrogenase 2) enzyme efficiently break down acetaldehyde, a toxic byproduct of alcohol metabolism, preventing the accumulation that typically causes symptoms like flushing, nausea, and rapid heartbeat. According to the study “Tolerance to Alcohol: A Critical Yet Understudied Factor in Alcohol Use Disorder Risk” by Elvig and McGinn, individuals with higher innate or acquired alcohol tolerance exhibit fewer immediate symptoms, which may partly explain their resistance to the unpleasant effects associated with alcohol intolerance. 

Additionally, a large-scale genetic study by Chvilicek-Seguin et al. revealed that complex interactions among multiple genes regulate alcohol sensitivity, and certain protective genetic configurations can reduce the body’s reactivity to alcohol. In short, some people are biologically better equipped to metabolize alcohol without triggering an immune or toxic response, which is why they do not experience typical symptoms of alcohol intolerance.

What are the causes of alcohol intolerance?

The underlying reasons for alcohol intolerance stem from several contributing elements that affect the onset of the condition. The causes of alcohol intolerance include the following:

1. Sulfites or other preservatives

Alcoholic drinks frequently contain preservatives like sulfites to prolong shelf life and retain freshness. Some individuals are sensitive to sulfites, leading to signs such as facial flushing, headaches, or respiratory difficulties.

The body treats these substances as irritants, prompting an inflammatory response that worsens alcohol intolerance symptoms. Those with asthma are especially vulnerable to reactions caused by sulfites, making certain drinks particularly troublesome.

2. Chemicals, grains, or other components

Alcoholic beverages are made with a range of ingredients, including grains, additives, and synthetic flavorings, that can trigger intolerance in some people. Components such as wheat, barley, rye, or corn can cause digestive upset or symptoms similar to allergies in sensitive individuals.

Other additives-like artificial colors or stabilizers-can further irritate the system and add to overall discomfort. Those with grain-related allergies or intolerances often face bloating, nausea, or nasal congestion after drinking specific alcoholic beverages.

3. Histamine

Fermented alcoholic drinks such as wine and beer are rich in histamine, which affects immune and allergic responses. Individuals with enzyme deficiencies that limit histamine breakdown may experience symptoms like migraines, nasal congestion, or skin irritation after drinking.

Elevated histamine in the blood causes blood vessels to expand, resulting in facial flushing and a sensation of warmth. Some people use prescription or over-the-counter antihistamines prior to drinking to try to minimize their symptoms, but the underlying intolerance typically remains unchanged.

What are some diseases that cause alcohol intolerance? 

Certain medical conditions can cause or worsen alcohol intolerance by disrupting how the body processes alcohol or by increasing sensitivity to specific components in alcoholic beverages. One such condition is Hodgkin's lymphoma, which can cause pain in the lymph nodes after alcohol consumption, a rare but documented reaction. Liver diseases, particularly cirrhosis, impair the liver’s ability to break down alcohol, leading to the buildup of toxic byproducts like acetaldehyde and resulting in heightened sensitivity. 

Another condition, porphyria cutanea tarda (PCT), affects the body’s ability to produce heme, and alcohol can trigger flare-ups by increasing enzyme activity that leads to porphyrin buildup. Celiac disease can also mimic alcohol intolerance symptoms when gluten-containing alcoholic beverages are consumed, causing inflammation and gastrointestinal discomfort. Additionally, histamine intolerance can make individuals react strongly to alcoholic drinks like wine and beer, which naturally contain histamines. People with this condition may experience flushing, headaches, or nasal congestion shortly after drinking. Identifying and managing the underlying condition is key to reducing alcohol-related symptoms.

What are the risk factors for alcohol intolerance?

Risk factors for alcohol intolerance are traits or health conditions that raise the chances of experiencing negative reactions to alcohol. The risk factors for alcohol intolerance include the following:

• East Asian descent: Genetic variations in East Asian populations result in reduced levels of aldehyde dehydrogenase (ALDH2), the enzyme vital for breaking down acetaldehyde, a toxic byproduct of alcohol. A 2008 study by Duranceaux et al., “Ethnic Differences in Level of Response to Alcohol Between Chinese Americans and Korean Americans,” reported that Korean Americans had a lower self-reported level of response to alcohol compared to Chinese Americans, suggesting they required more alcohol to feel its effects. Additionally, Koreans showed a higher prevalence of first-degree relatives with alcohol dependence (12.2%) compared to Chinese (1.3%). Place of birth (U.S. or abroad) did not significantly affect alcohol response.
• Asthma or allergic rhinitis: Those with asthma or allergic rhinitis tend to have increased sensitivity to alcohol. Alcohol intolerance is more pronounced in these individuals, making consumption unpleasant. People affected should pay close attention to alcohol intake, as there is a recognized link between alcohol and respiratory complications. Steering clear of certain alcoholic beverages or specific ingredients can lower the risk of adverse reactions.
• Hodgkin’s lymphoma: Alcohol-induced pain is a rare but recognized symptom in those with Hodgkin's lymphoma. As described in a 2013 report by Andrew J. Bryant and John H. Newman, “Alcohol intolerance associated with Hodgkin lymphoma,” the reason for alcohol-triggered pain remains unclear, but may involve vasodilation within swollen lymph nodes. Another theory involves prostaglandins, chemicals linked to inflammation and pain, since discomfort reduces with ibuprofen, which inhibits prostaglandin production.
• Grain allergies: People with grain allergies-such as to wheat, barley, or corn-can be intolerant to alcohol, particularly drinks like beer made from these grains. Ingesting grain proteins can cause allergic responses, including digestive upset or skin rashes. Alcoholic beverages containing these allergens often result in bloating, nausea, or hives. The immune system reacts to grain proteins as if they were threats, leading to inflammation and discomfort.

Does alcohol sensitivity increase with age?

Yes, alcohol intolerance can increase as you age. A key factor is the reduction in muscle mass that often accompanies aging. Since muscle tissue absorbs and disperses alcohol, less muscle leads to higher alcohol concentrations in the blood, resulting in stronger effects from smaller amounts.

Liver efficiency also diminishes with age, which slows the breakdown of acetaldehyde-a toxic byproduct of alcohol metabolism. Additional age-related changes further heighten alcohol intolerance. For example, slowed metabolism causes alcohol to have a prolonged impact, even if drinking patterns remain steady.

Aging also reduces the body’s water content, raising blood alcohol concentration (BAC) because alcohol becomes more concentrated in the bloodstream.

Lower enzyme levels further affect alcohol tolerance. With fewer enzymes available to metabolize alcohol, it takes longer for the body to process it, causing longer-lasting intoxication and more severe hangovers.

Are some ethnic backgrounds less affected by alcohol?

Yes, some racial groups have greater alcohol tolerance due to genetic differences that influence alcohol metabolism. Caucasians typically display higher tolerance, as ancestral enzyme adaptations allow them to break down alcohol more efficiently.

A 1986 review by Arthur W.K. Chan, “Racial differences in alcohol sensitivity,” reported that facial flushing-a sign of alcohol sensitivity-occurred in only 3–29% of Caucasians, compared to 47–85% among Oriental (East Asian) populations.

Is it possible to manage or reduce alcohol intolerance?

No, alcohol intolerance cannot be overcome. There is currently no cure for this condition, as it mainly stems from genetic factors that prevent the body from processing alcohol efficiently. No available treatment can change how alcohol is metabolized, so those with intolerance will always be prone to adverse reactions.

Although antihistamines or antacids may reduce some symptoms, they do not remedy the underlying cause. Some individuals try to gradually increase their tolerance by consuming small amounts of alcohol over time, but this approach does not resolve the metabolic issue and can actually raise the risk of serious health problems, such as certain cancers and heart disease.

The most effective way to manage alcohol intolerance is to avoid alcohol or keep intake to a minimum, opt for beverages with lower alcohol content, and stay alert to symptoms like flushing, nausea, dizziness, and rapid heartbeat.

What is the best alcohol for alcohol intolerance?

Gin is considered the most suitable alcohol for those with alcohol intolerance. This clear spirit has low histamine content and is free of sulfites-both common triggers for intolerance reactions in people sensitive to certain alcohol additives.

While gin does not treat asthma or allergies, choosing lighter-colored spirits like gin can help lower the risk of intensifying symptoms. In comparison to beer, wine, and darker liquors, gin is less likely to cause side effects such as flushing, nasal stuffiness, or skin irritation. Vodka is another option, especially when high-quality, unflavored varieties are selected, as they further reduce exposure to potential irritants.

What are effective ways to manage symptoms of alcohol intolerance?

Managing alcohol intolerance symptoms means minimizing or controlling the negative reactions that occur after drinking alcohol. The ways you can get rid of alcohol intolerance symptoms include the following:

• Avoid alcohol completely: The most reliable method for eliminating symptoms is to abstain entirely from alcoholic beverages. Because alcohol intolerance is rooted in genetics, no medical treatment can reverse the condition. Selecting non-alcoholic options prevents common reactions like flushing, nausea, and headaches. Total avoidance guarantees no contact with troublesome substances.
• Choose low-histamine and sulfite-free options: People with mild alcohol intolerance can benefit from drinks that have fewer histamines or preservatives. Clear spirits such as gin and vodka generally contain fewer irritants than beer or wine. Careful selection of beverages can help lessen uncomfortable side effects.
• Eat before and during drinking: Eating food helps slow alcohol absorption and reduces irritation in the digestive tract. Meals high in protein, fiber, or healthy fats act as a protective buffer for the stomach. A nutritious diet can ease symptoms like nausea or dizziness. Drinking on an empty stomach typically makes intolerance reactions worse.
• Use preventative medication: Those managing alcohol intolerance may find relief with antihistamines, antacids, or enzyme supplements to ease their reactions. These medications can counteract histamines or decrease stomach acid buildup. It’s important to consult a healthcare professional for safe and proper use.
• Stay hydrated: Drinking sufficient water assists in flushing toxins out of the body and can soften the impact of symptoms. Since alcohol is dehydrating, it can worsen headaches and dizziness. Alternating alcoholic drinks with water maintains hydration, which supports improved tolerance and reduces discomfort.
• Avoid alcohol with high additive content: Many alcoholic beverages contain sweeteners, stabilizers, or preservatives that can trigger intolerance. Opting for drinks with fewer additives helps lower the chance of adverse effects. Lighter, more natural alcohol choices are usually less irritating. Checking ingredient labels allows for the avoidance of aggravating substances.

Does naturally metabolizing alcohol allow the body to overcome its effects?

Yes, naturally metabolizing alcohol allows the body to gradually overcome its effects, but only to a limited extent and over time.

The liver breaks down alcohol through enzymes, primarily alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), which convert ethanol into acetaldehyde and then into acetate, a harmless substance excreted by the body. This metabolic process helps reduce the intoxicating and toxic effects of alcohol. However, the rate of metabolism is relatively fixed (about one standard drink per hour) and cannot be significantly accelerated by external methods like drinking water, eating food, or sleeping.

If a person consumes alcohol faster than their body can metabolize it, the effects, including intoxication, impaired coordination, and slowed reaction times, will accumulate. In people with alcohol intolerance or enzyme deficiencies (e.g., inactive ALDH2), this process is disrupted, and toxic byproducts like acetaldehyde build up, causing stronger or more immediate adverse effects. Thus, while metabolism does help the body eventually recover, it cannot prevent or instantly reverse alcohol’s impact, especially in those with underlying metabolic limitations.

How does alcohol intolerance differ from an alcohol allergy?

No, alcohol intolerance differs from alcohol allergy, just as metabolic reactions differ from behavioral conditions like why alcohol is addictive, which involve reward circuitry in the brain. Intolerance is a metabolic issue caused by the body’s inability to adequately break down alcohol, usually due to enzyme deficiencies. In contrast, an alcohol allergy involves the immune system mistakenly identifying alcohol or its ingredients as threats.

While intolerance leads to discomfort, allergic reactions are typically more severe and can rarely become life-threatening. Understanding the difference between alcohol intolerance and alcoholism is essential for effective symptom management and informed decisions about alcohol use.

How can you tell if it's alcohol intolerance or an allergic reaction?

Identifying alcohol intolerance versus an allergy depends on the symptoms you notice. Alcohol intolerance generally leads to discomfort like flushing, nausea, or nasal congestion, as the body struggles to metabolize alcohol efficiently.

In contrast, an allergy prompts an immune system response, resulting in more severe symptoms such as swelling, difficulty breathing, or pronounced skin irritation. Allergic reactions are typically more serious and potentially dangerous than the milder, though still uncomfortable, effects of intolerance.

Seeking medical advice is important to determine the underlying cause and to receive guidance on safe symptom management.

What are the differences between alcohol intolerance and alcohol allergy?

Distinctions between alcohol intolerance and alcohol allergy highlight how the body responds differently to alcoholic drinks. The differences between alcohol intolerance and alcohol allergy are shown in the table below.

Differences Between Alcohol Intolerance and Alcohol Allergy

‍

Understanding these differences helps individuals make informed choices to manage their symptoms. Knowing the specific cause and biological response is crucial for safer alcohol consumption decisions.

Are there any benefits of drinking alcohol? 

Yes, moderate alcohol consumption has been associated with certain health benefits, though these effects vary by individual and depend heavily on quantity and context.

Research suggests that moderate intake, typically defined as up to one drink per day for women and up to two for men, may contribute to improved cardiovascular health. This includes potential benefits like increased HDL (good) cholesterol levels, reduced blood clot formation, and lower risk of coronary artery disease. Red wine, in particular, contains antioxidants such as resveratrol and flavonoids, which may help protect the lining of blood vessels and reduce inflammation. Additionally, some studies have linked light to moderate alcohol use with a reduced risk of type 2 diabetes and ischemic stroke. Alcohol in low doses may also provide mild stress relief or social relaxation for some individuals. However, it’s important to note that these benefits do not outweigh the risks for everyone, and alcohol should never be used as a health strategy without considering personal and family medical history.

‍