Allergic contact dermatitis is a rash that develops as the result of an allergic reaction to a substance to which the skin is exposed. Unfortunately, it is often not apparent which specific substance is responsible. It usually takes detective work by both the patient and the physician. Patch testing is the cornerstone of this investigative process.
Patch testing is recommended for patients whose rashes are suspected to be the result of an allergy to substances that have come into contact with their skin. It consists of the application of a series of substances to the back, followed by a period of observation (2-4 days) to determine if rashes develop at the sites of contact.
Choosing the Right Substances
The approximately 80 patches that we have chosen to apply in our panel contain the substances that most commonly cause allergic rashes. It is an expanded version of the panel of allergens recommended by the North America Contact Dermatitis Group, a universally respected source of information regarding contact dermatitis.
Three separate appointments will be required for the entire patch testing procedure. If you are scheduling by phone, be certain to inform our staff that you have been instructed by your doctor to schedule "patch testing." There will be an initial appointment on a Monday for the application of the patches. The patches will be applied to your back with adhesive strips, and you will be asked to keep the area dry for the first 48 hours. There will be two test reading appointments later in the week, one on Wednesday and one on Friday. Patients are asked to follow up with a telephone call with their doctor two weeks after the test.