Permanent hair dyes cause contact urticaria, anaphylaxis

Palm Beach, Fla. - Paraphenylenediamine, or PPD, the main chemical used in permanent hair dye colors, is the third most common cosmetic allergen, preceded by preservatives (No. 1) and fragrances (No. 2), James S. Taylor, M.D., said at annual meeting of the Noah Worcester Dermatological Society.