There are a number of diagnostic tools that can be used to determine if a patient is allergic to wheat and to narrow down the allergy to specific wheat components. These tests can be performed and supervised by an allergy specialist. Allergy clinics, some hospitals, and other types of medical centers may offer screening for wheat and other potential allergens. It can take several weeks or months to correctly diagnose an allergy in someone who has a wheat allergy because these allergies tend to be complex.
People who are allergic to wheat can react with a number of different proteins found in wheat. Symptoms of wheat allergies can range from intestinal distress after eating wheat to full-blown anaphylaxis, where the patient's airways close in response to allergen exposure. Many people notice wheat allergies because they start developing skin conditions, digestive problems, runny nose, and a variety of other mild symptoms when they eat a lot of wheat.
The first step in allergy diagnosis is often a food and activity diary. Patients keep track of what they eat and what they do and note down any symptoms or changes in status as well. This can allow a doctor to start linking particular triggers with allergies. If a food diary shows that wheat-containing products are eaten around the time of allergy outbreaks, it can be a sign that a patient is allergic to wheat.
Someone who is allergic to wheat may be encouraged to try an elimination diet. The patient cuts back the diet to very bland foods and then carefully introduces new foods and takes note of the response. When the patient experiences an allergic reaction, the last foods consumed can be targeted as potential allergy culprits. For someone who is allergic to wheat, it is critical to read food labels carefully during an elimination diet because many foods contain wheat where it might not be expected. Soy sauce, for example, is sometimes produced with wheat.
A skin prick test can be performed where the patient is exposed to specific allergens and the response is monitored. Such testing is usually safe because the allergen doses are very small, but patients still need to be monitored in case they react poorly. Another option is a challenge test that involves eating small amounts of concentrated allergens. Blood testing can be used as well, and may be recommended if a doctor is concerned that skin prick or challenge tests could endanger a patient.