Photoallergic and allergic contact dermatitis from dibenzoylmethanes.

Dibenzoylmethanes are widely used in Europe in UVA-absorbing sunscreens. We found that 2 of these, 4-isopropyl-dibenzoylmethane and 4-tert.butyl-4'-methoxy-dibenzoylmethane caused allergic or photoallergic contact dermatitis. This is the first report on allergic and photoallergic reactions caused by dibenzoylmethanes.