Evidence-based review of lasers, light sources and photodynamic therapy in the treatment of acne vulgaris

Background There is a considerable need for effective and safe treatment for acne vulgaris. Objective In a systematic review with an evidence‐based approach to assess the effects of optical treatments for acne vulgaris. Methods Original publications of controlled clinical trials were identified through searches in PubMed and the Cochrane Library. Results A total of 16 randomized controlled trials (RCT) and 3 controlled trials (CT) were identified, involving a total of 587 patients. Interventions included photodynamic therapy (PDT; 5 RCTs), infrared lasers (4 RCTs), broad‐spectrum light sources (3 RCTs, 1 CT), pulsed dye lasers (PDL; 2 RCTs, 1 CT), intense pulsed light (IPL; 1 RCTs, 2 CTs), and potassium titanyl phosphate laser (1 RCT). The randomization method was mentioned in 6 of 16 RCTs, and one trial described adequate allocation concealment. Most trials were intraindividual trials (12 of 19), which applied blinded response evaluations (12 of 19) and assessed a short‐term efficacy up to 12 weeks after treatment (17 of 19). Based on the present best available evidence, we conclude that optical treatments possess the potential to improve inflammatory acne on a short‐term basis with the most consistent outcomes for PDT [up to 68% improvement, aminolevulinic acid (ALA), methyl‐aminolevulinic acid (MAL) and red light]. IPL‐assisted PDT seems to be superior to IPL alone. Only two trials compare optical vs. conventional treatments, and further studies are needed. Side‐effects from optical treatments included pain, erythema, oedema, crusting, hyperpigmentation, pustular eruptions and were more intense for treatments combined with ALA or MAL. Conclusion Evidence from controlled clinical trials indicates a short‐term efficacy from optical treatments for acne vulgaris with the most consistent outcomes for PDT. We recommend that patients are preoperatively informed of the existing evidence, which indicates that optical treatments today are not included among first line treatments.