A retrospective review of 20% vs. 10% incremental narrowband UVB regimens to treat psoriasis in skin phototypes III-V Koreans.

Background: The optimal incremental dose regimen of narrowband UVB (NBUVB) phototherapy that will provide maximal efficacy and safety has not been determined for patients with brown skin and psoriasis.

Objective: To compare 20% and 10% incremental dose regimens of NBUVB phototherapy with respect to efficacy and safety in Korean patients with brown skin and psoriasis whose Fitzpatrick skin phototypes (SPT) are III-V.

Method: A retrospective study was designed to compare the 20% and 10% incremental dose groups with respect to the number of sessions, duration of treatment, maximum dose, cumulative dose until response, and adverse effects.

Results: The mean number of sessions was significantly lower, the duration of treatment was significantly shorter, and the maximum dose was significantly higher in the 20% incremental dose group. The cumulative dose was not significantly different between the two groups, and there was no statistically significant difference between the groups with respect to the percentage of total adverse effects.

Conclusion: Use of a 20% incremental dose regimen could be advantageous over a 10% incremental dose regimen in patients with brown skin and psoriasis because of a faster treatment response and higher efficacy without a significant increase in the risk of adverse effects.