Outpatient phototherapy for psoriasis.

Using a new protocol with varied exposure increments, we found that, in 18 of 20 patients with psoriasis vulgaris who were given ultraviolet (UV)-B phototherapy three times a week, the disease completely cleared. One patient's condition substantially improved, and one patient's condition failed to respond. Ten to 38 treatments were required during a three- to 13-week period. The only topical treatment agent used was white petrolatum. The results are compared with a schedule using five treatments a week and fixed UV-B--exposure increments. Infrequent (three times weekly) treatments, avoidance of hospitalization and crude coal tar treatment, and fewer episodes of UV-radiation burn may offer advantages for selected patients. Long-term effects and maintenance requirements for this treatment regimen are not known.