Food Allergies and Food Intolerance
Diagnosing Food Allergies continued...
The advantage of such a challenge is that if the patient has a reaction only to suspected foods and not to other foods tested, it confirms the diagnosis. Someone with a history of severe reactions, however, cannot be tested this way. In addition, this testing is expensive because it takes a lot of time to perform and multiple food allergies are difficult to evaluate with this procedure.
Consequently, double-blind food challenges are done infrequently. This type of testing is most commonly used when the doctor believes that the reaction a person is describing is not due to a specific food and the doctor wishes to obtain evidence to support this judgment so that additional efforts may be directed at finding the real cause of the reaction.
The Exercise-Induced Food Allergy
At least one situation may require more than the simple ingestion of a food allergen to provoke a reaction: exercise-induced food allergy. People who experience this reaction eat a specific food before exercising. As they exercise and their body temperature goes up, they begin to itch, get light-headed, and soon have allergic reactions such as hives or even anaphylaxis. The cure for exercised-induced food allergy is simple -- not eating the suspected food for a couple of hours before exercising.
Treatment for Food Allergies
The main treatment for food allergies is dietary avoidance. Once a patient and the patient's doctor have identified the food to which the patient is sensitive, the food must be removed from the patient's diet. To do this, patients must read lengthy, detailed ingredient lists on each food they are considering eating. Many allergy-producing foods such as peanuts, eggs, and milk, appear in foods one normally would not associate them with. Peanuts, for example, are often used as a protein source and eggs are used in some salad dressings. The FDA requires ingredients in a food to appear on its label. People can avoid most of the things to which they are sensitive if they read food labels carefully and avoid restaurant-prepared foods that might have ingredients to which they are allergic.
In highly allergic people even minuscule amounts of a food allergen (for example, 1/44,000 of a peanut kernel) can prompt an allergic reaction. Other less sensitive people may be able to tolerate small amounts of a food to which they are allergic.
Patients with severe food allergies must be prepared to treat an inadvertent exposure. Even people who know a lot about what they are sensitive to occasionally make a mistake. To protect themselves, people who have had anaphylactic reactions to a food should wear medical alert bracelets or necklaces stating that they have a food allergy and that they are subject to severe reactions. Such people should always carry two syringes of adrenaline (epinephrine), obtained by prescription from their doctors, and be prepared to self-administer it if they think they are getting a food allergic reaction. They should then immediately seek medical help by either calling the rescue squad or by having themselves transported to an emergency room. Anaphylactic allergic reactions can be fatal even when they start off with mild symptoms such as a tingling in the mouth and throat or gastrointestinal discomfort.