Comparison of the minimal phototoxic dose in topical 4,5', 8-trimethylpsoralen PUVA treatment of caucasian skin and of oral mucous membrane.

Abstract

The minimal phototoxic dose values for UVA radiation of psoralen-treated skin and of oral mucous membrane were studied in 16 healthy volunteers. A commercial 0.01% trioxalen ointment was used as the topical photosensitizer. In all 16 persons the radiation dose needed to induce erythema was greater for the buccal mucosa than for the skin, and the average buccal minimal phototoxic dose was 2.3-fold that of the cutaneous minimal phototoxic dose.