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

This systematic review and meta-analysis evaluated the efficacy and safety of lasers and energy-based devices (EBDs) in treating androgenetic alopecia (AGA), involving 3,298 patients across 37 studies. Low-level light therapy (LLLT) increased hair density by 18.56 hairs/cm² and shaft thickness by 10.62 µm compared to sham treatments. Fractional laser monotherapy showed a more substantial increase in density (102.23 hairs/cm²) and a moderate increase in thickness (5.93 µm). Combination protocols with fractional lasers and agents like minoxidil, PRP, or growth factors resulted in even greater improvements in hair density (+33.6 hairs/cm²) and thickness (+11.22 µm), with global photographic improvement rates of 77.2% for monotherapy and 95.3% for combination treatments. Adverse events were mild and transient, indicating that LLLT and fractional lasers are effective and safe for AGA, especially when combined with other treatments.