A true alcohol allergy in which your body produces the antibody IgE in response to alcohol is very rare. Sensitivity to the effects of alcohol or alcohol intolerance is much more common. Symptoms of an actual alcohol allergy are just like those of other food allergies, including tingling in the mouth; swelling of the lips, tongue, or throat; hives; and difficulty breathing. For those who have a true alcohol allergy, less than an ounce of alcohol can send a person into anaphylactic shock.
Hidden Allergens in Alcohol
It's possible that those who experience food allergy symptoms when they consume alcohol are allergic to other ingredients in the alcohol, such as wheat or preservatives called sulfites. Beers may contain hops, barley, rye, corn, or wheat. In addition, yeast could be the cause of a reaction to alcohol. Interestingly, yeast actually produces histamine during the fermentation process. This histamine, the same chemical released during an allergic reaction, can be responsible for allergy symptoms such as hives, sneezing, and wheezing.
Egg proteins or seafood proteins are used as fining agents in some wines and beers; this may leave trace amounts of allergens behind, so people allergic to eggs or seafood need to be careful. Always check labels and inquire of servers. A recent trend to foam cocktails up with the inclusion of raw egg whites also poses threats to those who are allergic to eggs.
An alcohol intolerance, much more common than a true allergy to alcohol, is characterized by headache, nasal congestion, rapid heartbeat, nausea, vomiting, heartburn, abdominal pain, or warm, red, itchy skin. Those of Asian descent are particularly likely to have an alcohol intolerance due to a genetic disorder that makes the body unable to completely break alcohol down.
Sulfites and Alcohol Allergy
One reason that many people react to wine is their sulfite content. Sulfites are used as a preservative in wine, and are generally found in much higher concentrations in white wine than in red. (This is because the tannins present in red wine are natural preservatives.) In addition, cask wine contains higher sulfite levels than bottled wine. Asthmatic responses also occur when sensitive individuals encounter sulfites such as sodium metabisulphite in wine or beer. Wines and beers without added sulfites do exist, but low levels of sulfites may exist even in these wines. Organic wines are usually the best bet.
Foods That May Trigger an Alcohol Allergy
Those who do have an alcohol allergy must not only abstain from any alcoholic beverages, but must also be aware of the other foods that may contain alcohol and stay away from those as well. For instance, liqueur in candies can be extremely dangerous to an alcohol allergic individual. In addition, alcohol in combination with another allergen may produce an allergic response. This is sometimes called a "co-factor" response, and increases the likelihood of anaphylaxis from other causes.