RT Book, Section A1 Hardin, J. Matthew A2 Knoop, Kevin J. A2 Stack, Lawrence B. A2 Storrow, Alan B. A2 Thurman, R. Jason SR Print(0) ID 1181044022 T1 Allergic Contact Dermatitis T2 The Atlas of Emergency Medicine, 5e YR 2021 FD 2021 PB McGraw-Hill PP New York, NY SN 9781260134940 LK accessemergencymedicine.mhmedical.com/content.aspx?aid=1181044022 RD 2024/04/18 AB Allergic contact dermatitis occurs after previously sensitized skin is rechallenged with the same allergen and represents a delayed-type hypersensitivity reaction. Papules and vesicles first develop; they can become a generalized morbilliform eruption (autosensitization). Pruritus is a dominant feature. The most common causes are nickel, toxicodendrons (poison ivy, poison oak, and poison sumac), neomycin, fragrances, balsam of Peru (common in perfumes), formaldehyde, bacitracin, and rubber compounds.