Scratch Test for Allergies

What is the test?

This test checks for a skin reaction to common allergy-provoking substances, such as foods, molds, dust, plants, or animal proteins. If your skin reacts to a substance, chances are that you are allergic to it.

Most people with allergy symptoms don't need testing because they can identify their triggers and control their symptoms with medicine. Your doctor might recommend scratch testing when you have severe allergy symptoms but are not sure what is causing them. Knowing what you are allergic to can help you avoid the substance in the future, and will help your doctor determine whether you might benefit from allergy shots.

How do I prepare for the test?

Don't take antihistamines for three days before the test, because they can interfere with the results by preventing you from reacting to a substance you would normally be allergic to. Tell your doctor if you have ever had anaphylaxis, a life threatening allergic reaction, or if you have had a serious reaction to a previous allergy test.

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