Clinical and experimental photosensitivity reaction to tilisolol hydrochloride

This report describes a patient who developed a photosensitivity reaction during the treatment of hypertension with tilisolol hydrochloride, which is a beta-blocker agent Although the data are insufficient to distinguish photoallergy and phototoxicity, clinical and histologic features suggested that the mechanism involved was photoallergic in nature. The action spectrum was mainly the ultraviolet A range. The reaction was reproducible on oral readministration of the drug and exposure to a low dose of UVA. Photopatch testing with the drug was also positive only in the patient. Although the experimental photoallergic reaction was not induced in the guinea pig, phototoxic potential was demonstrated in the animal. To our knowledge, a photosensitivity reaction due to tilisolol hydrochloride has not been previously reported in the English literature.