Abstract
BACKGROUND: Botulinum toxin type A is widely utilized for both therapeutic and aesthetic purposes, yet concerns regarding its immunogenicity have raised issues related to treatment failure and adverse reactions. OBJECTIVE: This review aims to evaluate the immunogenicity of commercially available botulinum toxin type A products across various clinical indications and identify the risk factors associated with antibody formation. METHODS: A comprehensive search of electronic databases was conducted to find studies that investigated the immunogenicity of botulinum toxin type A in patients treated for different conditions. The studies were classified based on the Oxford Center for Evidence-Based Medicine's evidence hierarchy. RESULTS: The overall incidence of neutralizing antibody formation with botulinum toxin type A treatment is relatively low. However, it varies depending on the indication and is influenced by factors such as the frequency of injections and the cumulative dose. The total cumulative dose and the number of treatment cycles are critical factors in determining the risk of developing antibodies against botulinum toxin type A. CONCLUSION: This literature review highlights that the immunogenicity of botulinum toxin type A products differs across indications, with repeated injections posing a significant risk for the formation of neutralizing antibodies. The findings underscore the need for further research to better understand antibody formation mechanisms and to develop strategies that minimize their impact on treatment efficacy.