The Efficacy of Botulinum Toxin in the Treatment of Androgenetic Alopecia: A Meta‐Analysis

Background Androgenetic alopecia (AGA) is a chronic progressive disorder that may lead to permanent hair loss and associated psychosocial issues if left untreated. Although botulinum toxin (BTX) has been proposed as a potential therapeutic option for AGA, the evidence regarding its efficacy remains controversial. Objectives This study aims to evaluate the efficacy of BTX monotherapy for AGA through a systematic review and meta‐analysis. Methods We conducted a comprehensive search of PubMed, Embase, and the Cochrane Library to identify randomized controlled trials (RCTs) utilizing BTX for AGA treatment. The primary outcome was hair density (hair count/cm 2 ). Results A total of 7 studies involving 232 treatment units were included. The pooled within‐group change showed a mean increase of 24.51 hairs/cm 2 (95% CI: 10.22, 16.76) following BTX treatment. Subgroup analyses indicated that a significant increase in hair density was observed after 6 months of treatment, with an optimal injection dose of 100 U. Reinjection every 6 months was associated with significant hair density improvement. In addition, male participants demonstrated a more pronounced increase in hair density compared to mixed‐gender cohorts ( p = 0.0003). The therapeutic effect of BTX was more reliably estimated in studies with larger sample sizes. Conclusion BTX monotherapy yielded significant within‐group improvements in hair density and diameter among AGA patients. Subgroup analyses indicated that 100 U dosing with 6‐month intervals may optimize therapeutic outcomes. These findings warrant validation in large‐scale, randomized, placebo‐controlled trials to establish definitive clinical utility.