Lasers and Energy-Based Devices in the Treatment of Androgenetic Alopecia: A Systematic Review and Meta-Analysis.

Abstract

Introduction: Androgenetic alopecia (AGA) is a common progressive disorder with limited response to conventional pharmacological therapy. Energy-based devices (EBDs), including low-level laser therapy (LLLT) and fractional lasers, have emerged as minimally invasive alternatives or adjuncts to traditional treatments. We aimed to evaluate the efficacy and safety of lasers and EBDs in the management of AGA.

Methods: This is a systematic review and a meta-analysis that was conducted in accordance with PRISMA guidelines.

Results: A total of 3,298 patients were included across the 37 studies. Pooled analysis of LLLT demonstrated a mean increase in hair density of 18.56 hairs/cm² and shaft thickness of 10.62 µm compared with sham. When combined with minoxidil, LLLT yielded a greater improvement in hair density than minoxidil alone (mean difference +11.75 hairs/cm²). Fractional laser monotherapy, including ablative fractional CO₂ laser and non-ablative fractional laser, increased density by 102.23 hairs/cm² and thickness by 5.93 µm. However, combination protocols of ablative fractional CO₂ laser and non-ablative fractional thulium fiber and Er:glass laser with minoxidil, PRP, or growth factors produced a mean density increase of 33.6 hairs/cm² and a greater improvement in hair shaft thickness (+11.22 µm), along with a higher clinician-rated improvement rate (95.3% vs. 77.2% for monotherapy). Adverse events were mild and transient.

Conclusion: LLLT and fractional lasers are effective and safe for the treatment of AGA. However, fractional lasers, particularly when combined with topical agents such as minoxidil, PRP, or growth factors, demonstrate the most significant improvements in hair density and thickness, outperforming LLLT and monotherapy approaches.