Medical Health Encyclopedia

Injury Disease Nutrition Poison Symptoms Surgery Test Special Topic

1 2 5 A B C D E F G H I J K L M N O P Q R S T U V W X

RAST test Allergy skin prick or scratch test Intradermal allergy test reactions Skin testing, PPD (R arm) and Candida (L)

Overview Risks Results

Allergy testing

Alternative Names:

Patch tests - allergy; Scratch tests - allergy; Skin tests - allergy; RAST test

What the risks are:

Skin tests and food allergy tests carry a risk that you will experience an allergic reaction when exposed to the allergens. Some sensitive persons will (rarely) experience a life-threatening anaphylactic reaction.

Text Continues Below

---

Penicillin and closely related medications are the only drugs that can be tested using skin tests. Skin tests for other drugs are at best non-informative and can be dangerous.

Tests that are not proven as valid include cytotoxic testing, in which foods are mixed in a test tube with a sample of the person's blood and then the white blood cells are observed for a change in shape. Another unproven testing method is "provocation and neutralization" testing, in which the person is injected with a food or other substance and, if there is an allergic reaction, are injected with more of the substance to "neutralize" the response. This can be very dangerous!.

Special considerations:

The accuracy of allergy testing varies quite a bit. Even the same test performed at different times on a person may give different results. A person may react to a substance during testing, but never react during normal exposure. A person may also have a negative allergy test and yet still be allergic to the substance.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2004 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.