Allergy Testing and Asthma
If you are unable to determine what triggers your asthma symptoms, allergy tests might help. Contact your doctor to schedule an allergy testing- both skin tests and blood tests will work. Once testing is complete, your doctor will look at the results, as well as your history of allergic reactions in order to make a diagnosis. This diagnosis can put you on the right track to treating your asthma symptoms.
Allergy skin tests are a quick and inexpensive way of determining what your body is sensitive to. If you or your doctor believes that a specific allergen is causing your symptoms, a skin test will be best. These tests work by exposing your skin to high doses of potential allergens and monitoring how your immune system reacts to it. Prior to getting the testing done, ask your doctor if there is anything you need to do. Certain medications, like antihistamines, can alter the results of the tests.
There are three kinds of skin tests:
- Skin Prick Test: Your doctor will put several small drops of allergens on your back and then prick the skin where the drops are located with a needle. If a small, red, itchy hive appears where the prick was, you are allergic to that allergen. Skin prick tests are the most common tests used.
- Intradermal Test: If you believe your allergen may be environmental or drug related, intradermal tests are best. With this test, your doctor will inject your skin with the potential allergen. The downside to intradermal tests is that they can sometimes show false positives and can cause reactions that effect your whole body.
- Patch Test: Your doctor will put allergens on a patch and then place that patch on your skin on for 48 hours. You might be allergic to that allergen if your skin becomes irritated.
Blood tests are used less often and can be less effective than skin tests.
There are two kinds of blood tests:
- Radioallergosorbent Test (RAST): This test is for people with ultra-sensitive skin and will not be affected by medications you are like skin tests are. RAST is a more expensive and less accurate option.
- Quantitative Immunoglobulin Determination Test: This test helps doctors determine if your asthma symptoms are triggered by allergies by measuring levels of chemicals in your blood stream. This test is scarcely used.
Jaime Venditti, State Coordinator, New York Health Works