Different types of allergy testing can be used to identify various allergens. Some tests work better than others, depending on the allergy suspected. Therefore; be familiar with the various allergy tests available prior to making an appointment with your doctor. The tests available may fall into several categories including: Scratch tests, elimination tests, and blood tests.
Scratch Tests
The most common type of allergy testing that is done is the scratch tests. This test involves putting a small amount of the suspected allergen onto the surface of the skin, then scratch or prick the area to allow some of the substance to enter the surface.
Swelling, redness, or itching are signs that an allergic reaction has occurred. A result can often be detected in as little as twenty minutes using this type of testing. The other advantage to this kind of test is that many different allergens can be tested together. This makes this method especially useful if the allergen is unknown, airborne, or a food allergy.
Elimination Diets
Another type of allergy testing that is often performed is the elimination diet which is used if a food allergy is suspected. A variety of foods are eliminated from the diet for several weeks that are considered potential allergens.
This method of allergy testing works best with mild allergic reactions. However, it can pose a potential danger to patients who have severe, anaphylactic allergies. If there is a severe allergy suspected, a third method of allergy testing is preferred to ensure the safety of the patient. Thus, a life-threatening substance is not placed into the system of the allergy sufferer.
Blood Tests
The last type of allergy testing is the blood test, commonly called the RAST test. This is performed in the laboratory and uses blood that has been drawn for the patient. The blood is examined for presence of immunoglobulin antibodies. These will indicate if the body is producing an allergic reaction. Elevated levels of IGE's can tell your doctor if you are allergic to certain types of allergens. This method is not always accurate or precise as are the other methods. Should your doctor decide to have allergy testing done, he will examine your family medical history and tell you when to stop your medications.