Allergy testing is necessary to determine the cause of an allergic reaction. Allergies can evolve over time so it is important to identify the cause of the reaction before it grows to interfere with your life or become life threatening. For example, you would want to know that you have a food allergy before it causes your throat to swell closed or anaphylactic shock. Allergy testing can take several forms including skin prick and skin patch testings. These controlled tests expose the patient to a minute amount of a suspected allergen so that the body’s response can be monitored.
A skin prick test is also known as a “prick” test. In this test, the doctor or medical assistant will make a series of very small punctures on the arm with a plastic device that has 8 heads, and each head will deposit a specific allergen into the skin. Usually, the test will check for reactions to trees, weeds, grass, molds, pet dander, various foods and dust mites. If the mark next to an allergen forms a hive (red bump) after the evaluation period, it indicates a potential allergy to that substance. With this information in hand, the doctor can create an effective treatment plan. Skin testing typically takes about 30-45 mins and your results will be available immediately.
Allergic contact dermatitis occurs when the skin becomes patchy, scaly and inflamed when it comes in contact with a certain chemical substance. The allergen is not always known right away, so patch testing is the best way to identify it in many cases. These chemicals include nickel, preservatives, antibiotics, fragrances, and many others commonly used in household, personal hygiene, and cosmetic products. To perform the test, multiple common allergens are applied to the back in the form of patches, and the results are read 72-96 hours later.