Examining the Safety and Efficacy of Low-Level Laser Therapy for Male and Female Pattern Hair Loss: A Review of the Literature.

PURPOSE: Pattern hair loss is the most common type of alopecia. Standard of care involves long-term use of topical medications with limited effectiveness. Low-level laser therapy (LLLT) has become a popular alternative treatment. Here, we examine published clinical trials to establish whether the breadth of evidence supports LLLT for pattern hair loss. METHODS: A literature search was conducted within the PubMed, Embase, Scopus, and Cochrane Trials databases to identify original articles evaluating hair regrowth following LLLT. Articles were selected based on use of 600-1,100 nm wavelengths, treatment time ≥16 weeks, and objective evaluation for hair regrowth. RESULTS: Ten randomized controlled trials were included, of which 8 compared LLLT to sham device and 1 to no treatment. The study populations varied, with 3 studies evaluating only women. All sham-device controlled studies demonstrated statistically significant increase in hair diameter or density (p < 0.01) following LLLT. DISCUSSION: Based on our review of the literature, LLLT appears to be effective for treating pattern hair loss in both men and women. These laser devices have good safety profiles, with only minor adverse effects reported. However, physicians should be cautious when drawing conclusions as some studies included have a relationship with industry.