A comparative study of topical 5-aminolevulinic acid incubation times in photodynamic therapy with intense pulsed light for the treatment of inflammatory acne

BACKGROUND Photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) is used for effective treatment of facial acne vulgaris. OBJECTIVES To determine which of two different incubation times (30 minutes and 3 hours) is more effective in PDT with intense pulsed light (IPL) for acne vulgaris. METHODS & MATERIALS Twenty Korean subjects with moderate to severe acne were enrolled for a randomized, half-facial treatment study. Three sessions with short incubation with ALA plus IPL (30 minutes, n=9) or long incubation with ALA plus IPL (3 hours, n=11) on one side of the face and IPL alone on the other side were performed at 1-month intervals. RESULTS All subjects showed improvement in inflammatory acne lesions after three sessions of ALA-PDT or IPL alone (p<.001 in all groups). The degree of improvement in inflammatory acne lesions was greater in the long incubation time group than the short incubation time group or the IPL-alone group, although the mean reduction of inflammatory acne lesions was statistically different only between the long incubation group and the IPL-only group (p=.01). There were no statistical differences between the short incubation group and IPL-alone group. All three groups had decreased sebum secretion after three sessions (p<.001 in all groups), but the differences between groups were not statistically significant. Only transient erythema and mild edema were reported for all treatment groups. CONCLUSION PDT with a long ALA incubation time might be more adequate for a pronounced outcome with inflammatory acne. The authors have indicated no significant interest with commercial supporters.