Airborne contact dermatitis: common causes in the USA.

Airborne contact dermatitis (ABCD) is an inflammatory reaction involving the skin upon exposure to allergenic agents or irritants suspended in air. In allergic ABCD, the hypersensitivity is classified as a type IV reaction. Substances responsible for such reactions can be of plant or non-plant origin. Commonly reported plants include those of the Compositae family, which includes ragweed, goldenrod, and sunflowers. Establishing an accurate diagnosis is critical for preventing exposure and improving symptoms in patients. Obtaining a detailed history and performing a physical examination to determine the sites of involvement, as well as patch testing to establish the causative allergen, are the main methods of arriving at the correct diagnosis. Treatment often involves avoidance of the allergens or irritants when possible and may also include the application of topical barrier creams or systemic therapy in more severe cases. This article reviews the topic of ABCD and highlights its most common etiologies in the USA.