Background: Alopecia androgenetica is the most common type of hair loss. It is estimated that 60-70% of the world's population is affected, with men having a slight advantage. This condition supports a progressive hair thinning in androgen-sensitive zones, as defined by the Hamilton and Norwood classifications for men and Ludwig classifications for women. There are numerous published studies that show the effect of red light (650-675 nm) on hair growth biostimulation. Objective: To validate this correlation, the aim of this study was to assess the efficacy of 675 nm laser emission for the management of alopecia androgenetica in female and male subjects. Methods: A total of 17 subjects (6 women and 11 men) aged from 18 to 65 years, without other comorbidities, with an alopecia androgenetica grade ranges between I-II in women (according to Ludvig scale) and I-II-III in men (according to Hamilton scale) were enrolled in the study between October and December 2021. All patients underwent 10 sessions of 675 nm laser treatment, each lasting 20 min, without the use of concomitant systemic or topical therapies. Results: The results verified at epiluminescence stage, and at the third month of follow-up and at the end of treatment, showed a significant increase in the density of the hair shafts and a reduction of yellow dots and telangiectasias characteristic of alopecia androgenetica. Conclusions: The 675 nm laser showed excellent outcomes resulting in a 60% reduction of the miniaturization process in the treated areas without side effect.
Keywords: 675 nm laser; androgenetic alopecia; hair follicle; hair growth biostimulation.