Allergic contact dermatitis is responsible for approximately half of all contact dermatitis cases. Patients with persistent, unresolved contact dermatitis can suffer for years with a diminished quality of life and increased medical treatment costs. However, the condition can be effectively treated once an accurate diagnosis is obtained.

Patch testing is a simple procedure to help diagnose allergic contact dermatitis and identify the causative agent(s).


The ultimate goal is to assist patients suffering from dermatitis to become better informed consumers and be cognizant of potential allergic contact triggers of the rash.

Patch test consists of panels of a wide variety of different allergens including fragrance, preservatives, metals, rubber ingredients, and other chemicals that one may commonly encounter in the surrounding and household items. Patch test involves no pain and requires a visit in 2 days to removal patch test panels and usually another visit in one to few days afterwards to catch potential delayed reactions.

Patch test is different from skin prick allergy tests performed by allergists. Skin prick allergy tests are helpful for allergic rhinitis or asthma as they will help elucidate type I immediate-type hypersensitivity. However, skin prick allergy tests are rarely helpful for skin sensitivities as type IV delayed-type hypersensitivity is typically involved. Patch test is designed specifically to isolate potential delayed-type hypersensitivity from contact triggers which is most relevant for allergic contact dermatitis.