Alcohol intolerance test: Causes, symptoms, and methods

Last updated: 20 February 2023

There’ll be plenty of flushed cheeks, but for some of you, they don’t necessarily happen because you’ve had a few glasses of red wine. They might mean you have alcohol intolerance. If that’s the case, a few drinks might have worse consequences than a hangover.

In this article, we’re going to discuss what causes alcohol intolerance, different alcohol intolerance test methods, and what you can do if you are alcohol intolerant.

In this article

What’s the difference between an intolerance and an allergy?
What causes alcohol intolerance?
How can your genes cause alcohol intolerance
Alcohol intolerance symptoms and when do they occur
Alcohol intolerance test: Which one to take?
DNA test
Clinical tests
#1 A skin prick test
#2 Blood test
#3 Ethanol patch test
Home “test”
What to do if you are alcohol intolerant?

What’s the difference between an intolerance and an allergy?

But first, we should clarify the difference between an intolerance and an allergy. A food or drink intolerance means either the body cannot properly digest a particular food or liquid, or that it might irritate the digestive system.

Symptoms of food or drink intolerance are uncomfortable and can make you feel ill, but are generally not very dangerous. They include nausea, gas, cramps, diarrhoea, and headaches.

You can discover if you’re genetically predisposed to alcohol intolerance with our DNA test! Click on the photo below to learn more.

A food or drink allergy is a different story. It happens when the body’s immune system gets involved. It sees the food or liquid as an invader and it responds by releasing chemicals like histamine – that’s what we call an allergic reaction.

Such a reaction can cause more serious or even life-threatening symptoms like breathing problems, throat tightness, vomiting, swelling, or a drop in blood pressure.

Fortunately, most people who have a reaction to alcohol aren’t allergic to it. They have alcohol intolerance. As you’ll see, the reasons behind it can be very different.

What causes alcohol intolerance?

There are quite a few factors that appear to increase the likelihood of alcohol intolerance. Here are the most common ones:

  • enzyme deficiency,
  • being asthmatic,
  • having a diagnosis of Hodgkin’s lymphoma or damaged liver,
  • being of East Asian descent as this group is more prone to enzyme deficiency.
  • sulfites,
  • various preservatives,
  • ethanol as it increases gut permeability, allowing toxins and bacteria to pass into the bloodstream.

You may also have an inflammatory reaction to a certain ingredient in your alcoholic drink of choice. Most often, people are intolerant to:

  • grapes,
  • hops,
  • wheat, barley, rye, and grains,
  • yeast which ferments the alcohol,
  • seafood, egg, or fruit proteins present in beverages,
  • histamines.

The different causes are important when you’re choosing your alcohol intolerance test and how to handle the symptoms. To understand what exactly is happening in your body in some cases, especially when talking about an intolerance caused by enzyme efficiency, you should understand the role of your genes.

How can your genes cause alcohol intolerance

The reason for alcohol intolerance can be the defect of the gene which codes the enzyme ALDH2. This enzyme is responsible for the breakdown of acetaldehyde – an intermediate product in ethanol metabolism, which is even more toxic than ethanol itself. The defect of the ALDH2 gene causes your body to produce less active ALDH2, which prevents it from digesting alcohol properly. Acetaldehyde accumulates and causes alcohol intolerance.

Enzyme ADH1 is also important for alcohol metabolism. It is responsible for the first step of alcohol metabolism; converting ethanol into acetaldehyde. Researchers have discovered that a mutation can also occur in the genes that encode the ADH1 enzyme, which greatly influences the efficiency of ethanol conversion to acetaldehyde. Genetic variants increase ADH1 enzyme activity leading to the build-up of toxic acetaldehyde.

Alcohol intolerance symptoms and when do they occur

If you’re intolerant to alcohol, you might experience certain signs and symptoms that occur after drinking. Note that alcohol intolerance does not mean you will become intoxicated faster than others, but that you will have a negative and unpleasant reaction to alcohol.

Generally, you see symptoms occur shortly after consuming alcohol – in about 20 or 30 minutes. Symptoms can persist for one or two hours, but keep in mind that every person and situation are different, and not everyone will experience alcohol intolerance the same way and severity. Some may encounter immediate reactions.

If you have alcohol intolerance, you may encounter one or several of these symptoms:

  • flushed face,
  • diarrhoea,
  • feeling hot,
  • headache,
  • dizziness,
  • heartburn,
  • hives (red bumps on your skin),
  • rashes,
  • faster heart rate or palpitations,
  • low blood pressure,
  • stuffy or runny nose,
  • stomach pain, which can lead to nausea or vomiting,
  • shortness of breath.

If you have asthma, your alcohol intolerance symptoms will be worse than usual.

However, if you have an alcohol allergy, you can experience more serious symptoms and severe reactions. Pay attention to the following symptoms and be ready to call an ambulance if they suddenly get worse:

  • rashes,
  • swelling,
  • difficulty breathing,
  • throat tightness,
  • stomach cramps,
  • vomiting,
  • drop in blood pressure,
  • loss of consciousness,
  • anaphylaxis, which is a severe allergic reaction that can include a rapid, weak pulse, nausea, and vomiting. You should immediately call an ambulance.

If you have been encountering any of the intolerance symptoms after drinking alcohol or are avoiding it because of it, you probably know you’re alcohol intolerant.

What you might not know is what is causing your intolerance. If you want to find out, you can take an alcohol intolerance test. Let’s see the options you have at your disposal.

Alcohol intolerance test: Which one to take?

DNA test

The analysis of your DNA will let you know if you have an unfavourable variant of ALDH2 or ADH1 gene (or even both), which can cause acetaldehyde build-up and consequently, alcohol intolerance. The main advantage of our metabolism-related DNA test is that it analyses more than just alcohol metabolism. You can discover if you might also be intolerant to some other substances like caffeine, gluten, and lactose. You can see what a Diet and nutrition chapter includes here.

Clinical tests

Alternatively, you can visit your doctor and undergo one of the clinical tests.

Your doctor will probably start by asking you questions about your symptoms and medical history, such as:

  • Which alcoholic beverages trigger your symptoms?
  • What symptoms do you experience?
  • When did you start getting symptoms?
  • Do you have a family history of allergies?
  • Do you have any other medical conditions?

Then they’ll decide which test will help them understand what it is that you’re intolerant to. It may be ethanol or it might be ingredients in certain drinks that are causing you discomfort.

Here are the 3 most common tests:

#1 A skin prick test

This is a physical exam where your doctor will use a lancet to prick or scratch your skin. They will apply a drop of an allergen extract to the pricked or scratched area. Your skin’s reaction will let them determine whether you might have an allergy to something in alcoholic beverages — for example, the grains in beer. If you’re allergic to the substance being tested, you’ll develop a raised bump or a similar skin reaction.

#2 Blood test

This test measures your immune system’s response to a particular substance by checking the amount of immunoglobulin E antibodies in your bloodstream. A blood sample is sent to a laboratory to check reactions to certain allergens. This test determines allergies and isn’t always accurate.

#3 Ethanol patch test

During this test, your doctor places a drop of ethanol on a gauze pad and tapes it to your arm, waits about seven minutes and then removes the gauze and checks for signs of redness, itching, or swelling. This can help them determine if you’re allergic to ethanol.

Home “test”

There’s also a test you can do at home on your own if you have only mild symptoms. First, stop drinking all alcoholic beverages for at least a few days. Then try your go-to drinks one-by-one separated by a day or two and observe your reaction. That way you’ll see if you’re only intolerant to certain drinks and might guess which ingredients cause the reaction. You might also discover that you’re simply alcohol intolerant and have a reaction to anything that contains it.

What to do if you are alcohol intolerant?

If you have an alcohol allergy or are experiencing strong symptoms, you shouldn’t be drinking alcohol. Unfortunately, there’s no way around as even a small amount of alcohol can trigger a strong reaction.

If you don’t tolerate a specific ingredient in certain alcoholic products, you can drink beverages without it. Make sure that they don’t contain it and you’re good to go. For example, you might not tolerate barley which is often found in beer. But there’s no barley in red or white wine, so they shouldn’t cause a reaction.

If you’re experiencing mild symptoms, but would still like to drink a glass or two, there are certain measures that can help you alleviate the reaction.

If you know that your metabolism isn’t efficiently digesting alcohol, you should drink slower and give it more time in order to prevent acetaldehyde build-up. Mixing or diluting your drinks with non-alcoholic beverages also helps as well as drinking plenty of water as it helps to eliminate alcohol and its metabolites from your body. Obviously, if you want to avoid any symptoms, you should avoid alcoholic beverages altogether.

That’s it. Now you know what causes alcohol intolerance, what symptoms to observe, and what are different alcohol intolerance test options. Even if you’re not alcohol intolerant, always remember to drink responsibly and please don’t take any unnecessary health risks.

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