Efficacy and Safety of Botulinum Toxin Type A in the Treatment of Trigeminal Neuralgia

Abstract

Objective: This review aims to analyze the current data for the use of botulinum toxin type A (BTX-A) in the treatment of trigeminal neuralgia (TN) and highlight the evidence for its efficacy and safety. Pain management in patients with TN is challenging, as facial pain often does not respond well to conventional therapies. BTX-A has been suggested as a potential treatment option, but there is limited evidence regarding its long-term efficacy. Methods: A comprehensive search was conducted in various databases (PubMed, Scopus, Embase, ClinicalTrials and Cochrane Library) to identify clinical studies evaluating the use of BTX-A in TN until October 2023. Randomized controlled trials, single-arm studies, and stratified studies were included in the analysis. The mean difference (MD), effect size (ES), and 95% confidence interval (CI) were estimated for visual analogue scale (VAS) scores, pain attack frequency and the proportion of responders. Results: The analysis included 23 studies, including four randomized controlled trials, fourteen single-arm studies, and five stratified studies. In the randomized controlled trials, BTX-A was found to significantly reduce mean VAS scores compared to baseline (ES: -4.05; 95% CI: -6.13, -1.97; P=0.002). In nineteen non-RCTs, the pooled single-arm analysis revealed that BTX-A decreased VAS scores (ES: -5.19, 95% CI: -6.05, -4.33, P<0.001) and pain attack frequency (ES: -17.85, 95% CI: -23.36, -12.34, P<0.001) from baseline to the end of follow-up. The overall proportion of responders to BTX-A treatment was also significant (95%CI: 0.653, 0.761, P=0.003). Discussion: Current evidence indicated BTX-A injection is an effective and safety option for patients with refractory TN or not responding to medical or surgical management. However, more high-quality studies are needed to further confirm its efficacy.