Allergic Contact Dermatitis - Allergens

Allergens

Common allergens implicated include the following:

• Nickel (nickel sulfate hexahydrate) - metal frequently encountered in jewelry and clasps or buttons on clothing
• Gold (gold sodium thiosulfate) - precious metal often found in jewelry and dental materials
• Balsam of Peru (Myroxylon pereirae) - a fragrance used in perfumes and skin lotions, derived from tree resin (see also Tolu balsam). It may also be a component of artificial vanilla and/or cinnamon flavorings.
• Chromium - used in the tanning of leather. Also a component of uncured cement/mortar, facial cosmetics and some bar soaps.
• Oily coating from plants of the Toxicodendron genus: poison ivy, poison oak, and poison sumac.
• Thimerosal - a mercury compound used in local antiseptics and in vaccines
• Neomycin - a topical antibiotic common in first aid creams and ointments, cosmetics, deodorant, soap and pet food. Found by itself, or in Neosporin or Triple Antibiotic
• Fragrance mix - a group of the eight most common fragrance allergens found in foods, cosmetic products, insecticides, antiseptics, soaps, perfumes and dental products
• Formaldehyde - a preservative with multiple uses, e.g., in paper products, paints, medications, household cleaners, cosmetic products and fabric finishes. Often released into products by the use of formaldehyde releasers such as imidazolidinyl urea, diazolidinyl urea, Quaternium-15, DMDM Hydantoin and 2-bromo-2-nitropropane-1,3-diol.
• Cobalt chloride - metal found in medical products; hair dye; antiperspirant; metal-plated objects such as snaps, buttons or tools; and in cobalt blue pigment
• Bacitracin - a topical antibiotic found by itself, or as Polysporin or Triple Antibiotic
• Quaternium-15 - preservative in cosmetic products (self-tanners, shampoo, nail polish, sunscreen) and in industrial products (polishes, paints and waxes).
• Colophony (Rosin) - Rosin, sap or sawdust typically from spruce or fir trees
• Topical steroid - see steroid allergy
• Photographic developers, especially those containing metol
• Topical anesthetics such as pramoxine or diphenhydramine, after prolonged use
• Methylchloroisothiazolinone/Methylisothiazolinone is a preservative used in wash-off products such as shampoos/conditioners.