Allergic contact dermatitis is a T-cell dependent, delayed-type (Type IV) hypersensitivity reaction that has a high impact both in terms of patient morbidity and economics. This type of hypersensitivity reaction is primarily instigated by small lipophilic chemicals (haptens) with a molecular weight less than 500 Daltons. These chemical allergens trigger a complex immunologic cascade in the skin, which leads to the clinical picture of nickel allergic contact dermatitis.