Studies in adults show that pretreatment with an optimal
emollient may improve transmission of ultraviolet-B. In our study, we evaluated whether the preirradiation use of
mineral oil enhanced the efficacy of narrow-band ultraviolet-B
phototherapy in childhood
psoriasis. Twenty children, aged 5 to 14 years with widespread, symmetrical
psoriasis involving >20% body surface area were enrolled in a prospective, single-blind, controlled study.
Mineral oil was applied prior to irradiation over one half of the body and the other half was
emollient-free control. Narrow-band ultraviolet-B
phototherapy was administered to whole body twice a week on nonconsecutive days with initial dose of 50 mJ/cm(2) and increment of 10% at each session. Clinical response was evaluated as grades of
erythema, scaling and induration, area of involvement and modified
psoriasis area severity index score on each side at baseline, 3, 6, 9, and 12 weeks. Two patients dropped out, 18 patients completed the study. Significantly greater improvement (p < 0.05) in scaling, induration, area of involvement, and modified
psoriasis area severity index score was seen on the
mineral oil pretreated side as early as 3 weeks and was maintained throughout the study. Difference in
erythema was noticed later at 6 weeks. The cumulative dose for clearance was significantly lower on the
emollient pretreated side. No adverse effects were observed with
mineral oil or narrow-band ultraviolet-B
phototherapy. We conclude that preirradiation use of
mineral oil enhances the therapeutic efficacy of narrow-band ultraviolet-B
phototherapy in children with widespread
psoriasis.