Efficacy of Botulinum Toxin in the Treatment of Cutaneous Flushing: A Systematic Review and Meta-Analysis

BACKGROUNDFlushing is a common dermatologic complaint and can be resistant to many treatments. As the utility of botulinum toxin continues to expand, recent data suggest that it may also be a therapeutic option for flushing.OBJECTIVETo evaluate the efficacy of botulinum toxin for the treatment of cutaneous flushing.MATERIALS AND METHODSA systematic search of Medline, Embase, Cochrane CENTRAL, CINAHL, Scopus, and Web of Science databases was conducted to identify studies evaluating the effect of botulinum toxin on flushing 1 month after treatment. Prespecified outcome measures included a clinical flushing score, dermatology life quality index (DLQI), and erythema index (EI). Meta-analysis was performed to calculate the mean differences in these outcomes before and after treatment at 1-month follow-up.RESULTSNine studies (132 patients) were included in the analysis of this study (2 randomized controlled trials and 7 nonrandomized studies). All studies had a low risk of bias (high quality). The most frequent outcome reported was a clinical flushing score, which significantly decreased by 1.25 points overall (95% confidence interval [CI]: -2.47; -0.04) 1 month after treatment with botulinum toxin. Mean DLQI scores decreased (i.e., improved) by 9.02 points (95% CI: -19.81; 1.77) 1 month after botulinum toxin injections. The EI (measured by Mexameter) before and after botulinum toxin was evaluated in 2 studies; however, not enough statistical information was provided to analyze with meta-analytic techniques.CONCLUSIONBased on this meta-analysis, botulinum toxin significantly improves clinical flushing scores 1 month after treatment.