16 patients with summer-exacerbated dermatitis were examined by patch testing and photopatch testing with a battery of Compositae and standard allergens. IgE and RAST, and the thresholds to UVA and UVB, were determined. 6 female and 2 male patients showed allergic contact reactions to one or more Compositae extracts from flowers common in Sweden, also used in skin care products. The study points to the importance of including testing with Compositae allergens in patients with summer-exacerbated dermatitis. This group comprises patients with multiple contact reactions, photosensitivity and flares of atopic dermatitis.