Pityriasis versicolor is a common chronic superficial fungal infection caused by the organism Malassezia furfur. Although many conventional treatments have been shown to be successful in treating pityriasis versicolor, therapy of long-term duration may be needed in many cases, and recurrence is not uncommon. In vitro experimental investigations have demonstrated that several fungal strains can be effectively inactivated by irradiation with visible light wavelengths in the presence of photosensitizer.1- 3 However, to our knowledge, there have been no clinical trials of photodynamic therapy (PDT) against pityriasis versicolor.
Kim YJ, Kim YC. Successful Treatment of Pityriasis Versicolor With 5-Aminolevulinic Acid Photodynamic Therapy. Arch Dermatol. 2007;143(9):1209-1226. doi:10.1001/archderm.143.9.1218