The Efficacy and Safety of Botulinum Toxin A for the Treatment of Rosacea: A Systematic Review.

The off-label use of botulinum toxin type-A (BoNT-A) in treating rosacea seems encouraging, but the evidence is still lacking regarding its efficacy and safety. This study was conducted to summarize the evidence regarding the efficacy and safety of BoNT-A in the treatment of rosacea patients. A comprehensive literature search was conducted in several databases, and 17 studies were included. Before-after and split-face comparisons showed that BoNT-A significantly alleviated the symptoms of facial erythema and flushing and improved the patient's quality of life/satisfaction. However, the symptoms recurred three to six months post-injection, requiring repeated treatments in some patients. The pooled rates of post-injection localized erythema, ecchymosis, and facial muscle affection represented 24.6%, 5.1%, and 4.3%, respectively. BoNT-A seems to be effective in alleviating the symptoms of rosacea with a low rate of adverse events. However, the recurrence of the symptoms a few months after the injection requires repeated sessions, which may raise cost-effectiveness issues. Large-scale clinical trials are required to confirm the effectiveness and define the optimal dosing regimen and the rate of recurrence. Future studies should allow for an adequate follow-up after the treatment, with repeated measurements of the outcomes.