Narrow-band UV-B phototherapy: An effective and reliable treatment alternative for extensive and recurrent pityriasis versicolor

Purpose: In the previous studies, positive effect of sunlight on seborrheic dermatitis may well be explained by the direct influence of UV-light on the yeasts. Narrow-band ultraviolet-B phototherapy appears to be a very effective and safe treatment option for patients with severe seborrheic dermatitis. We aimed to investigate the efficacy of narrow-band ultraviolet-B phototherapy as an alternative treatment for pityriasis versicolor. Material and methods: A total of 38 patients diagnosed with disseminated pityriasis versicolor having more than four relapsing episodes within 12months were treated with narrow-band ultraviolet-B phototherapy given three times weekly. Clinical assessment on the basis of the severity of pruritus, erythema/hyperpigmentation and scaling and mycological examination were made at Weeks 0, 4, 8, 12 and 16. Results: Of the remaining 30 patients, 20 (66.7%) achieved excellent results and four patients (14%) had mild residual disease. The decrease in the clinical scores calculated at 4th week, 8th week, 12th week and 16th week were statistically significant. Conclusion: Narrow-band ultraviolet-B presumably may have an immunomodulatory and inhibitory effect on Malassezia growth. Narrowband ultraviolet-B is an effective and safe alternative tool for the management of extensive and recurrent pityriasis versicolor for patients who are unresponsive to conventional treatments.