Allergy skin testing allows us to evaluate which specific environmental allergen, insect venom, or medication patients may have a sensitivity to. Skin testing elicits a response of the allergy antibody, IgE, on histamine releasing immune cells known as mast cells. The test involves introducing allergens into the skin, and when patients are sensitive to a particular allergen, redness and swelling will appear in the test area. The larger the reaction, the more severe the sensitivity.
Types of skin allergy testing:
Percutaneous (prick or scratch) testing:
This is the most commonly used skin test for allergy testing. A small amount of allergen is introduced into the skin on the point of a small needle. After a brief wait, the testing areas are examined and measured for the presence of redness or swelling that would indicate a positive reaction. Prick testing is an excellent method for determining which patients are good candidates for treatment with allergy shots and which might do best with avoidance strategies.
This type of testing involves deeper injections of allergens into the skin resulting in a much more sensitive test for allergies. Intradermal testing is often used to clarify inconclusive percutaneous results and is the method of choice to identify stinging insect venom allergies and medication allergies.