What is an Allergy Patch Test?

The allergy patch test is a specialized diagnostic procedure used to identify specific substances that cause allergic skin reactions, such as contact dermatitis. This test is different from other allergy tests that detect immediate allergic responses. Instead, it is designed to reveal delayed allergic reactions, which can occur hours or even days after contact with an allergen. By applying patches containing potential allergens to the skin, typically on the back, and observing any reactions over a period of 48 hours, the test helps in pinpointing the exact triggers of allergic responses.

How Does the Allergy Patch Test Work?

During an allergy patch test, small adhesive patches that contain various potential allergens are applied to your skin, usually on your back. These patches are adhered with hypoallergenic tape to ensure they stay in place for a duration of 48 hours. After this period, the patches are carefully removed, and your skin is examined for immediate reactions such as redness, swelling, or blistering. The test is designed to detect delayed allergic responses, so a follow-up examination is typically scheduled 48 hours after the patches are removed. This additional check helps to identify any delayed reactions that may not be apparent immediately but could indicate an allergy to specific substances.

Benefits of the Allergy Patch Test