[Photoallergic reaction to olaquindox].

Olaquindox, an antibiotic belonging to the quinoxaline group, is a growth promoter used in pig breeding. A farmer developed a photoallergic contact eczema to it, which progressed to a persistent light reaction. Besides this, we found a photosensitivity to chlorpromazine, a tranquillizer that is also used in pig breeding. In addition, after using potent light-protective drugs containing UV-A and UV-B filters, this patient developed a (photo)allergy to different filter substances. The photoallergy to olaquindox was caused by mixing a food additive containing olaquindox with the pigswill for both young and adult animals. We point out the dangers (potent photoallergen, cancer induction) resulting from the widespread use of this substance in the EC.