Botulinum toxin for chronic rhinitis: A systematic review and meta-analysis

Background Botulinum toxin type A (BTX-A) is a potential treatment for chronic rhinitis. This study aimed to assess the effectiveness and safety of BTX-A in treating patients with chronic rhinitis. Methods Systematic searches of MEDLINE, Scopus, and EMBASE databases were performed. Randomized controlled trials (RCTs) that assessed the efficacy of BTX-A in allergic rhinitis and/or nonallergic rhinitis patients, compared with either placebo or active treatment, were included. The outcomes were total nasal symptom (TNSS), disease-specific quality of life (QOL), and adverse events. Results Nine RCTs (340 patients) met the eligibility criteria. Compared with placebo, the <= 12-week effects favored BTX-A injection on TNSS (standardized mean difference [SMD] -2.22, 95% confidence interval [CI] -3.27 to -1.17, p < 0.01, four RCTs). Beneficial effects > 12 weeks over placebo (MD -9.69, 95% CI -11.29 to -8.09, p < 0.01, one RCT) were demonstrated up to 24 weeks. However, the benefits were not shown on nasal congestion and individual nasal symptoms. Compared with active comparators (triamcinolone injection, ipratropium bromide, and cetirizine), there was no difference in the < 12-week effect between groups on TNSS. There was no difference between BTX-A and cetirizine on QOL (one RCT). The > 12-week effects on TNSS and individual nasal symptoms favored BTX-A over triamcinolone injection (one RCT). The risk ratio of adverse events favored BTX-A over cetirizine (one RCT). Conclusions BTX-A improved TNSS and QOL in patients with chronic rhinitis. These effects were demonstrated up to 24 weeks post treatment. BTX-A was safe, well tolerated, and may be considered in patients who are refractory to current standard-of-care therapies.