title: Experimental studies on the mechanism of benoxaprofen photoreactions.
abstract: Benoxaprofen (BP), a non-steroidal antiphlogistic drug causing skin and nail photoreactions, has been evaluated for photoactivity using three experimental techniques. In vivo in the mouse, BP was phototoxic in doses of 25 mg/kg in combination with UV-A 54J. The phototoxic potency could be confirmed in vitro with the Candida albicans test. In vitro, using photohemolysis, BP showed a dose-dependent activity causing 40% hemolysis at a concentration of about 25 micrograms/ml with UV-A. Also, small UV-B doses caused red cell lysis with a moderate BP concentration. Pre-irradiation experiments showed that UV-A, but not UV-B, photoproducts could account for some of the activity. The action spectrum of BP photoactivity lies mainly in the UV-A, but may also extend into UV-B. Compared with chlorpromazine in vivo and in vitro, and with doxycycline in vivo, BP showed intermediate phototoxic activity.
mesh_terms: D000818:Animals; D002176:Candida albicans / Q000187:drug effects; D002746:Chlorpromazine / Q000633:toxicity; D005260:Female; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D051379:Mice; D010787:Photosensitivity Disorders / Q000139:chemically induced*; D011422:Propionates / Q000633:toxicity*; D014466:Ultraviolet Rays
chemical_list: D011422:Propionates; C011677:benoxaprofen; D002746:Chlorpromazine