Allergies are the result of the immune system having an abnormally strong reaction to a normally harmless substance. Depending on the type and severity of the allergy, patients may develop a skin rash, mild respiratory symptoms or a strong and potentially life-threatening reaction. Allergy testing works to identify the cause of allergies.
Indications
Both adults and children with allergies can be candidates for allergy testing, according to the American Association of Allergy Asthma and Immunology (AAAAI). Allergy testing may be recommended for patients who have respiratory symptoms, such as a runny nose or wheezing, as well as patients who develop skin rashes or hives in response to allergens. Patients who have gastrointestinal allergic symptoms such as pain, diarrhea and cramping may also need allergy testing. Allergy testing is especially important for patients who have strong allergic reactions that cause their throat to swell and impair breathing.
Common Tests
There are three main kinds of allergy testing, Medline indicates. Skin prick testing involves placing a small amount of potential allergens somewhere on the patient's skin, such as the forearm or back, then pricking the skin so that the allergen is able to get underneath. If a patient has an allergy, the skin will become red and swollen. Elimination tests are useful for food allergies and involve eliminating foods from the diet and then gradually reintroducing them to see if they cause allergic symptoms. Blood tests can look for antibodies to certain allergens and can be useful for patients who cannot receive skin prick tests.
Challenge Test
Challenge testing, the AAAAI explains, involves having the patient inhale or ingest a small amount of a suspected allergen. The patient is then monitored for symptoms of an allergic reaction, such as watering eyes, respiratory symptoms or swelling of the throat or face. This test needs to be done with caution and under the supervision of an experienced allergist because of the potential for a dangerous allergic reaction if the patient's allergy is severe.
Unproven Tests
There are a number of other tests that may be effective but are not recommended by the Asthma and Allergy Foundation of America because they are unproven. These include skin titration, urine auto-injection, electroacupuncture biofeedback, cytotoxicity blood testing and basophil histamine release. These tests may be able to diagnose some allergies but they are considered to be less reliable than other, more commonly used allergy tests.
Benefits
Allergy testing allows for the identification of allergens, which can be of great benefit to a patient. Not only can this allow patients to avoid substances that trigger allergies, the AAAAI explains that it also keeps patients from unnecessarily eliminating things from their life that are not causing allergic reactions.
