If you’ve been dealing with skin rashes for any length of time, your doctor will start by considering all the obvious causes. But if medicines don’t clear up your problem, they may eventually want you to undergo a skin patch test to determine what substances you’re allergic to.
A skin patch test lasts for several days, so you’ll need to follow some specific directions to make sure your test is completed properly and can give the best results.
Here are a few tips on how to prepare for skin patch testing from Dr. Sherwin Hariri and our team at Beverly Hills Allergy in Beverly Hills and Glendale, California.
What is skin patch testing?
Skin patch testing is exactly what it sounds like: using patches placed on your skin to find the cause of an allergic reaction. It can be very useful in identifying allergens that may be present in your environment, including substances like metals, dyes, chemicals, preservatives, rubber, fragrances, resins, and many more.
The test usually lasts for 4-5 days and can test for about 80 substances. On the first day, allergens are applied to special skin patches, which contain up to 10 substances, and are then placed on your back or arm and left on your skin for 48 hours.
When you return to the office in two days, Dr. Hariri removes the patches and looks for signs of an allergic reaction. Any reaction is noted, and then you go home and return to our office in two more days to check for further reactions.
How to prepare for skin patch testing
You’ll need to take several steps to prepare your skin for this kind of testing. Two to three weeks before your test, stop taking any immunosuppressive drugs you may have been prescribed, such as a steroid.
About a week before your test, begin avoiding sun exposure to your back and stop using any topical creams or medicines on your back or arms where the patches will be placed. (You can continue to use creams on other areas of your body.) Three days before your test, stop using any other lotions or moisturizers on your back.
As you may have guessed, the skin patches can’t get wet, so you can’t bathe, shower, or go swimming during your testing period. (You can use a washcloth or sponge on other areas of your body, but don’t get your back wet.) You also can’t participate in any activities that cause you to sweat. Too much water or sweat will cause the patches to come loose, which will invalidate the test.
If you think you may need skin patch testing, Dr. Hariri and our team at Beverly Hills Allergy are at your service. We have two Beverly Hills-area locations to serve you. Just set up an appointment at our office nearest you today by phone or book online.