Balsam of Peru: past and future.

: Balsam of Peru (BOP) is a well-known contact allergen that is one of the most prevalent in the United States. For some patients allergic to BOP, external avoidance of fragrance is not enough to eliminate their dermatitis. A BOP avoidance diet has been shown to help many of these patients. This article reviews BOP allergens found in food. A special patch test series of allergens found in BOP along with data regarding which foods contain specific BOP constituents makes it possible to design potential targeted, refined, and simplified diets for BOP systemic contact dermatitis.