title: Factors influencing methoxsalen phototoxicity in vitiliginous skin.
abstract: A series of experiments were conducted to determine the optimum conditions required to induce methoxsalen phototoxicity in vitiliginous skin. The results revealed that optimum phototoxicity could be obtained only when a lapse of at least 15 minutes was allowed between the application of the drug and exposure to long-wave ultraviolet light (UVA). The duration of methoxsalen's phototoxic potentially, after its application to skin, varied in direct proportion to chemical concentration. Although a high chemical concentration and low dosage of UVA was a less time-consuming method of inducing phototoxicity, our results indicate that lower concentration and longer UVA exposure were less likely to induce undersirable blistering reactions.
mesh_terms: D000287:Administration, Topical; D000328:Adult; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004341:Drug Evaluation; D006801:Humans; D008730:Methoxsalen / Q000008:administration & dosage* / Q000627:therapeutic use; D008875:Middle Aged; D010787:Photosensitivity Disorders / Q000139:chemically induced*; D013997:Time Factors; D014467:Ultraviolet Therapy; D014820:Vitiligo / Q000628:therapy*
chemical_list: D008730:Methoxsalen