Allergy Testing Defined

Allergy testing, also known as skin, prick or blood testing, is a method for determining to what substances a person is allergic.

Skin allergy testing is the most common, reliable and relatively painless form of allergy testing. A very small amount of certain allergens is put into your skin by making a small indentation or “prick” on the surface of your skin. A skin allergy test determines specific allergens based on skin reactions. You don’t have to wait long to find out what is triggering your allergies. Reactions occur within about 15 minutes.

If you have allergies, just a little swelling will occur where the allergen(s) which you are allergic to was introduced. For instance, if you are allergic to ragweed pollen but not to cats, only the ragweed allergen will cause a little swelling or itching. The spot where the cat allergen was applied will remain normal. 

Blood tests are generally used when skin tests might be unsafe or won’t work, such as if you are taking certain medications or have a skin condition that may interfere with skin testing.

There are methods of allergy testing that the American Academy of Allergy, Asthma & Immunology (AAAAI) believes are not useful or effective. These tests are performed by non-allergy practitioners or people who call themselves healthcare professionals but lack formal training and national board-certification in the field of allergy and immunology. For example, the American Academy of Allergy, Asthma & Immunology, and other professional bodies have recommended against using IgG testing to diagnose food allergies or food intolerances / sensitivities.

Learn more about which tests to avoid in the diagnosis of allergies.

If you or your child suffer from symptoms of allergy, an allergist / immunologist, often referred to as an allergist, can help. An allergist has advanced training and experience to properly test for allergens and develop a treatment plan to help you feel better and live better.

The AAAAI's Find an Allergist / Immunologist service is a trusted resource to help you find a specialist close to home.