Patch testing 101, part 2: after the patch test.

After the patch test, the physician must interpret positive reactions in the clinical context of the patient's dermatitis. Relevance can be graded as current, past, or unknown. Counseling the patient on allergen avoidance is the most important step, and resources such as allergen information sheets and physician-generated safe lists from product databases can be used to help the patient both understand their allergens and avoid further exposure.