[Exogenous photosensitizing agents]

The frequent use of remedies either in topical or systemic form has led to a rising number of photosensitizations. The different cutaneous manifestations of exogenous photosensitizers e.g. phototoxicity and photoallergy, are described. We treat the most important agents of these reactions and lay stress upon the patient's interview and the phototesting in order to find out the substance, that induced photodermatosis.