Botulinum Toxin for Scalp Conditions: A Systematic Review.

[BACKGROUND] Many reports have described the use of botulinum toxin (BTX) in the treatment of scalp conditions, but no studies have synthesized these collective findings.

[OBJECTIVE] We conducted a systematic review to summarize the scalp conditions for which treatment with BTX has been described.

[METHODS] We searched PubMed/MEDLINE and Scopus for articles in English published before November 1, 2022, using the keywords "hair" or "scalp" and BTX-related search terms. Articles that described patients who received injections of BTX for the management of scalp conditions were included.

[RESULTS] Twenty-four original articles (12 case reports, 9 clinical trials, and 3 case series) were identified that described 309 patients with a scalp condition treated with BTX. Androgenetic alopecia, craniofacial hyperhidrosis, and scalp hyperseborrhea had the most robust data supporting the clinical efficacy of BTX.

[CONCLUSION] The current quality of evidence is highly variable and, for many conditions, limited to small observational studies. Botulinum toxin may be a promising therapeutic option for patients with various scalp conditions, but future studies are needed to better understand its efficacy and safety.