Effectiveness and Safety of Intralesional Dutasteride in Patients With Androgenic Alopecia: A Systematic Review and Meta-Analysis.

BACKGROUND: Androgenic alopecia (AGA) is a common condition characterized by progressive hair loss influenced by dihydrotestosterone (DHT). While oral dutasteride has shown efficacy in treating AGA, concerns about systemic side effects have prompted interest in localized treatments such as intralesional administration. AIMS: This systematic review evaluates the effectiveness and safety of intralesional dutasteride for treating AGA in adults. METHODS: Following PRISMA guidelines, we conducted a comprehensive search of multiple databases for studies involving adults (≥ 18 years) with AGA treated with intralesional dutasteride. Eligible studies included randomized controlled trials, non-randomized studies, cohort studies, and observational studies. Exclusion criteria were animal studies, duplicate publications, and studies lacking relevant outcome data. The primary outcomes were improvements in hair density, hair thickness, and photographic evidence of hair growth. Secondary outcomes assessed safety, including local and systemic adverse events. Data extraction and quality assessment were independently performed by two reviewers. RESULTS: Included studies consistently reported improvements in hair density and thickness following intralesional dutasteride treatment, with photographic evidence supporting visual improvement. Treatment was generally well tolerated, with minimal adverse events such as mild scalp irritation and no significant systemic effects reported. However, the studies varied in methodology, sample size, and follow-up duration. CONCLUSIONS: Intralesional dutasteride appears to be a promising treatment option for AGA, offering localized efficacy with a favorable safety profile. Nonetheless, the current evidence is limited by heterogeneity and a lack of large-scale, high-quality trials. Further standardized research is needed to confirm these findings.