Trioxsalen bath plus UVA effective and safe in the treatment of psoriasis.

Seventy-four patients with psoriasis were treated using a trioxsalen bath (50 mg/150 l of water) and long wave ultraviolet light (UVA) given in an ordinary PUVA-cabin. Good or excellent results were observed in 92% of the patients in the initial phase and in 63% during the maintenance treatment. Because of local side-effects the therapy was discontinued in two patients. One of them developed contact hypersensitivity to trioxsalen and the other developed blisters with such low doses of UVA that it was difficult to maintain the proper dose. The therapy was started with 0.28 J/cm2 of UVA and after an average of 18 treatments, when the average dose was 1.70 J/cm2, the patients were moved to maintenance treatment which took place at 1--4 week intervals. The therapy was well tolerated and cosmetically very acceptable. The final tan was even on all but the face, which remained untanned.