Response of psoriasis to psoralen-UVB photochemotherapy

The effect of psoralen in combination with 31 1 nm (UVB) radiation was studied in five subjects with normal skin and 10 patients with psoriasis involving both forearms. Treatment with oral 8-methoxypsoralen augmented the UVB erythemal response at 6 h after irradiation, but had no effect at 24–72 h. In eight of the nine patients who completed the trial, lesions of psoriasis on the arms treated with psoralen-LlVB cleared hefore lesions on the arms treated with UVB alone. This study has shown that psoralen in comhination with UVB has an erythemal effect on normal skin, and a therapeutic effect in psoriasis which is greater than the response to UVB alone.