Lasers and Energy-Based Devices in The Treatment of Androgenetic Alopecia: A Systematic Review and Meta-analysis

Background: Androgenetic alopecia (AGA) is a common progressive disorder with limited response to conventional pharmacological therapy. Energy-based devices [EBDs], including low-level light therapy (LLLT) and fractional lasers, have emerged as minimally invasive alternatives or adjuncts to traditional treatments. We aim to evaluate the efficacy and safety of lasers and EBDs in the management of AGA. A systematic review and meta‑analysis were conducted in accordance with PRISMA guidelines. Summary: 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. 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, while combination protocols of ablative fractional CO₂ laser and non‑ablative fractional thulium fiber and Er Glass laser with minoxidil, PRP, or growth factors yielded greater improvements [density +33.6 hairs/cm²; thickness +11.22 µm]. Global photographic improvement rates were 77.2% for fractional laser monotherapy and 95.3% for combination protocols. Adverse events were mild and transient. Key Message: LLLT and fractional lasers are effective and safe for AGA, with the most significant outcomes observed when used in combination with other agents.