Efficacy of Minoxidil Combined With Photobiomodulation for the Treatment of Male Androgenetic Alopecia. A Double-Blind Half-Head Controlled Trial.

BACKGROUND: Androgenetic alopecia (AGA) is a hair loss disorder that frequently affects the male population. Conventional treatment modalities are limited to minoxidil, 5α reductase inhibitors, and hair transplantation procedures. The efficacy of low-level laser therapy (LLLT), also known as photobiomodulation, in the treatment of AGA has been reported, yet little is known about the outcomes of combining photobiomodulation with other conventional therapies. OBJECTIVE: To evaluate hair growth improvement in males with AGA, during the administration of minoxidil with and without photobiomodulation, using a half-head model. STUDY DESIGN/MATERIALS AND METHODS: Twenty-one men with AGA agreed to undergo 12 minutes of low-level laser irradiation (using a modified Capellux®), followed by topical minoxidil application (1 ml of 5% solution), to the affected scalp two times per day for 6 months. The photobiomodulation devices were modified such that the left half emitted light, and the right half did not. Efficacy was assessed by blinded analyses of clinical photos and automated phototrichograms (Trichoscan®) taken before treatment and after 3 and 6 months of therapy. RESULTS: None of the study participants experienced any adverse events. All patients showed improvements in hair coverage on both sides of the scalp at 3 and 6 months. On the side with combined treatments, the number of total hairs was significantly increased after 3 (P < 0.001) and 6 months (P = 0.001). A similar increase was also observed on the minoxidil-only side, at both 3 (P < 0.001) and 6 months (P < 0.001). No statistically significant differences were detected between sides (P > 0.05). CONCLUSION: Additional improvement was not observed with the association of photobiomodulation to topical minoxidil in male AGA. Differences from previous studies that might have influenced our result include non-collimated light source, higher dosimetry, and a cohort with darker skin phototype and more severe alopecia. Lasers Surg. Med. 2021. © 2021 Wiley Periodicals LLC.