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Skin and Patch Testing

Skin and patch testing can help to diagnose environmental, drug, and food allergies, as well as allergic skin conditions.

Why choose UPMC in Central Pa. for skin and patch testing?

The allergy specialists at UPMC Allergy and Immunology understand that allergies can be inconvenient, uncomfortable, and in some cases, potentially life-threatening. We provide skin and patch testing that can help to diagnose the cause of your allergy and help you get the right treatment for your condition.

Skin Testing

What is skin testing?

Skin testing, also called scratch testing, is a painless test that exposes your skin to small amounts of allergy-causing substances (allergens). Skin testing can identify pollen, animal, mold, penicillin, and food allergies.

What do I need to know before skin testing?

Your doctor will provide specific instructions about how you should prepare for skin testing.

What happens during skin testing?

In adults, skin testing is usually done on the forearms. In young children, skin testing is usually done on the back. Your health care provider will clean the testing area with alcohol wipes and mark the areas where the testing will be done.

Your health care provider will then use multiple plastic devices that each contain a different allergen to lightly scratch the top level of your skin. This scratching does not hurt, bleed, or leave a visible mark.

Skin test results take 15 to 20 minutes, and you will need to avoid touching the testing area during that time.

What can I expect after skin testing?

If your skin test is positive, a hive will develop at the site of the scratch within about 20 minutes. Bigger hives usually mean that you are more sensitive to the allergen. This hive will last at least an hour.

After your skin test, your doctor will discuss the results with you and develop an allergy treatment plan if necessary.

Patch Testing

What is patch testing?

Skin Patch Testing at UPMC

Patch testing involves applying an allergen to a patch that is placed on your skin. Patch testing is usually used to diagnose allergic reactions that take days to develop, latex allergies, or other allergies to medications, fragrances, preservatives, hair dyes, metals, or resins that cause skin reactions.

What do I need to know before patch testing?

Your doctor will provide specific instructions about how you should prepare for patch testing.

What happens during patch testing?

During patch testing, your doctor will apply the suspected allergen to a patch that is placed on your skin. The patch will remain on your skin for 48 hours and will be removed at the doctor’s office. Your doctor will give you instructions about how to care for the patch while you are wearing it.

What can I expect after patch testing?

If the test is positive, your skin at the patch site will be irritated. Based on the results of your patch test, your doctor will develop an allergy treatment plan for you.



Specialty Care ENT – UPMC
508 S. Washington Street
Gettysburg, PA 17325

Phone: 717-334-8171
Fax: 717-334-8172

Specialty Care ENT – UPMC
250 Fame Avenue
Suite 201, (Entrance A)
Hanover, PA 17331

Phone: 717-633-9229
Fax: 717-633-5552

UPMC Allergy and Immunology
Located at UPMC Outpatient Center
21 Waterford Drive
Mechanicsburg, PA 17050

Phone: 717-988-9180
Fax: 717-775-5723 


Need more information?

Many of our providers offer video visits. Call the office or schedule via your patient portal.

Phone: 717-988-9180

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