Topical methoxsalen photochemotherapy in the treatment of palmoplantar pustulosis and psoriasis.

Topical methoxsalen photochemotherapy has been assessed in 22 patients suffering from recalcitrant palmoplantar pustulosis or psoriasis predominantly involving the hands and feet. Although 20 out of 22 patients improved and good results were obtained in exactly half of those treated, only 4 patients were classified as being "clear" or "minimally involved" at the end of 12 weeks. Two patients have shown no improvement at all. Minor local side effects were relatively common and included symptomatic erythema, blistering and local pigmentation. The histological findings in post PUVA treated skin are discussed and the pros and cons of topical photochemotherapy in this group of diseases is reviewed.