Allergy and immunology experts may consult on issues involving asthma, allergic reactions, indoor environment, and drug allergies, among other topics. On his website allergy expert witness Dr. Ronald H. Saff, Assistant Clinical Professor of Medicine at the Florida State University College of Medicine in Tallahassee and principal at the Allergy & Asthma Diagnostic Treatment Center, answers questions on allergy skin tests:
How are skin tests done?
There are several different types of allergy tests. Most allergy skin tests are “scratch tests” – the skin is scratched with a small plastic “pick” which has a drop of the specific allergen on the end. It is irritating and can burn and or itch; it is not painful. Scratch tests do not involve needles or blood. The scratching may take only seconds or take a couple of minutes depending on what you are being tested for. Once the scratching is done we wait 15-20 minutes and then read the results. A positive reaction usually looks and feels like a mosquito bite. Sometimes scratch skin tests are followed by intradermal tests. These are not always necessary and depend on what is being tested. If necessary a tiny amount of allergen is injected into the skin with a very small needle. It is not like a typical “shot”. This too may itch or burn. One benefit of skin tests such as these is that the results are known before you leave the office.
Why are tests necessary?
For most patients, allergy skin testing is the reason why you were referred to an allergist and why you are seeking an evaluation. It is essential to know what you are and are not allergic to in order to guide treatment decisions. You may think you are allergic to something and we may find through testing that you are not allergic. Instead, it may be a different problem. Or, we may find you are allergic to more than you thought. Once we know what you are allergic to, we can discuss how to avoid or reduce exposure to the allergens which is the foundation of treatment. Knowing the results also helps in making medication decisions and will determine if immunotherapy (allergy shots) will be a treatment option for you. Refusing to be tested makes this specialty evaluation pointless. It would be like going to the dentist complaining of tooth problems and not allowing them to look in your mouth.