Inefficacy of topical methoxalen plus UVA for palmoplantar pustulosis.

The effect of local application of 8-methoxypsoralen (8-MOP) and subsequent UVA irradiation on palmoplantar pustulosis (PPP) was studied in 10 patients. In 8 patients 8-MOP baths were used, and in 5 patients an 8-MOP ointment was applied, 3 patients receiving both forms of treatment. The number of treatment sessions varied from 15 to 128, with maximal UVA doses of 1.2 to 12 J/cm2, and total cumulative doses of 8 to 348 J/cm2. Two patients experienced a brisk phototoxic erythema and one patient developed a bullous reaction. Only 3 patients responded favourably to the treatment, 2 with moderate and 1 with good clearing of the lesions. In the remaining 7 patients either no effect (5 patients) or an exacerbation of the disease (2 patients) was seen.