Contact Dermatitis is a localized rash or irritation caused by exposure to allergens (allergic contact dermatitis) such as metals, fragrances or certain cosmetic preservatives, irritants (irritant contact dermatitis) such as plants or harsh chemicals, or by an interaction between an otherwise unharmful or less harmful substance on the skin and sunlight (phototoxic dermatitis). The rash can be treated with use of antihistamines, barrier creams (with zinc oxide), or if more severe can be treated by a physician with the use of topical corticosteroids.