Skin Testing for Allergies
||Many people dread the idea of getting skin tested for allergies.
Getting "scratch-tested" sounds even worse than going to the
dentist. However, while the procedure may not be pleasant, it
is not painful, and generally does not require a great deal of time.
Here is a summary of available methods of skin testing for
allergies, and a bit of information which may make the process seem
a little less intimidating.
The intracutaneous method
In this method, the suspected allergen is injected into the skin of
your arm. The intracutaneous method is generally used for allergens
like insect venom or penicillin. Because its the most sensitive
test, it can yield false-positives the test involves a more
intense contact with the allergen then you'll encounter in daily
life. However, this is true for all the tests even though you are
allergic to a certain substance, you may not regularly exhibit
The epicutaneous method (also called the patch test)
In this method, the suspected allergen is applied to a patch or
bandage, which is placed against your skin for a longer period of
time, usually 48 hours, after which you'll return to your doctor for
evaluation. This method is generally used for skin-contact allergens
like latex, fragrances, dyes, or medicines.
The percutaneous method (also called the puncture, prick,
or scratch test)
This is the most common method, and is commonly used to identify
typical environmental allergens like pollen, mold, pet dander, dust
mites, and food allergens. This test is conducted by applying an
extract of an allergen to the skin, typically on the forearm or
back. The nurse or doctor uses a pen to mark areas on your skin, and
then places a drop of a different allergen in each area. Then, a
small pricking device like a blunt needle is used, so that the
extract can enter the outer layer of the skin. The skin prick does
not cause bleeding and is not painful, just mildly irritating.
After about 15 minutes, the doctor or nurse will look for signs of
an allergic response a red bump, surrounded by a red inflamed
area. If you test positive, your healthcare provider will discuss
treatments and solutions with you.
Return to the Allergy Relief Learning Center