Dermatological tests, also known as patch tests, are tests to see if the skin is reacting to certain substances. Patch testing is used to determine the cause of skin reactions such as allergic contact dermatitis.

How is patch testing done?

Preparation: First of all, the skin is cleaned. Then, small patches (patches) containing the suspected allergen are attached to the skin, usually on the back.

Standby Time: These patches usually stay on the skin for 48 hours. During this period, there is direct skin contact with the substance on the patch.

Reading: After 48 hours, the patches are removed and the skin is evaluated for any reaction. However, sometimes it may take longer for an allergic reaction to occur. Therefore, after the initial 48 hours, an additional reading is usually taken after 72 or 96 hours.

Evaluation: If a skin rash, blisters, itching or other reaction occurs, this individual is considered allergic to that substance.

There are some things to consider before and during the test:

The use of certain medications, such as allergy medications or corticosteroids, prior to the test may affect the test results. For this reason, you should inform your doctor about all the medicines you use.
During the test, water should not touch the patch area.
The test area should not be scratched.
Patch testing is usually done simultaneously against many different substances. This can help detect a specific allergen. However, it should be kept in mind that any test can be misleading and give false negative or false positive results.