Allergy patch testing is a common allergy testing method used to confirm the cause of allergic contact dermatitis in a patient. Allergy patch testing is also a preferred method for identifying delayed allergic reactions that may take several days to present and are known as type IV hypersensitivity reactions.

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It is an easy and topical process that involves little pain or inconvenience for a patient. All testing is done on the upper back so as not to limit a patient’s movement. The procedure involves no pricks or scratches to the skin.

Patch testing is a different procedure than skin prick testing. Skin prick testing is used by allergists to determine which foods or allergens are triggering an acute or immediate allergic reaction in a patient.

 

Patch testing, on the other hand, is used solely to determine whether a patient’s dermatitis is caused by some substance in the patient’s environment, including metals, preservatives, medications, etc