Allergies affect millions of people every day. Allergy testing by a trained allergy specialist can help identify the substances that affect you through skin tests, blood tests, or elimination diets. Before you undergo an allergy test, you will be asked about your lifestyle, as well as your family and medical history.
What Happens During an Allergy Test?
An allergy test is performed by a doctor who will expose you to a small amount of an allergen and then monitor your reaction.
You may experience some unpleasant feelings during testing, including common allergy symptoms such as sneezing, scratchy throat, shortness of breath, and watery eyes. In some cases, a more serious reaction may occur.
Types of Allergy Tests
Skin Tests
A skin test, the most common type of allergy testing, is used to identify environmental, food-related, and contact allergens. The main types of skin tests are scratch, intradermal, and patch.
Scratch Test
- During a scratch test, a liquid form of the allergen is placed on your skin; the outer layer of your skin is then scratched with a special tool. Your doctor will closely monitor your skin to see if any redness, swelling, or itchiness occurs.
Intradermal Test
- If scratch test results are unclear, your doctor may recommend an intradermal test. With this test, a doctor will inject a small amount of the allergen just under the skin and monitor your reaction.
Patch Test
- Patches filled with allergens are placed onto a section of your skin. A doctor will check the patches 48 and 72 hours after application.
Blood Test
A doctor may administer a blood test if you are taking medicine that could interfere with skin testing, or if you suffer from severe skin conditions. You also may undergo a blood test if there’s risk of a particular allergen causing a severe reaction.
In a blood test, your blood is drawn and tested for antibodies that fight specific allergens. Because your blood is sent to a lab for analysis, it may take longer to receive results.
Elimination Test
Your doctor may recommend an elimination diet to help determine which foods are bothering you. Certain foods will be removed from your diet for a period of time, then added back. The doctor will monitor your reactions to the dietary changes to help determine the cause of your allergy.
For more information about allergy testing, or to schedule an appointment, contact UPMC’s Comprehensive Allergy-Immunology Clinic at 412-648-6161.