Botulinum toxin A for the Treatment of Androgenetic Alopecia: A Review

Androgenetic alopecia (AGA) is a condition that predisposes patients to patterned hair loss across the scalp, significantly impacting self-esteem and mental health. Conventional treatments, including finasteride, a 5-alpha-reductase, and minoxidil, a topical vasodilator, have both shown inconsistent effectiveness and are associated with notable adverse effects. Botulinum toxin type A (BTA), a neurotoxin produced by the bacterium Clostridium botulinum, is widely used in cosmetic medicine for reducing facial wrinkles and is indicated for several medical conditions. It has been proposed that BTA may benefit patients with AGA by increasing scalp blood flow and reducing scalp tension, though these mechanisms remain under investigation. This narrative review evaluates the current literature on BTA and its effects on androgenetic alopecia, with emphasis on efficacy, safety, and use in combination with finasteride and minoxidil. A literature search of PubMed, Medline, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) Plus using the terms (Androgenetic alopecia) AND (Botulinum toxin) AND (Treatment) identified 86 articles, which were narrowed to 56 after initial screening; six of these were selected for inclusion based on their relevance to the review's objectives. All six articles reported that BTA was associated with increased hair growth as a standalone therapy and in combination with finasteride and minoxidil, with improvements in hair density, reduction in total hair loss area, and a favorable adverse effect profile. While BTA use for AGA remains in the early phases of investigation, the available evidence suggests a positive association between BTA and hair regrowth in AGA. Further research is needed to fully establish its role in the management of this condition.