Effect of ondansetron compared to lidocaine and placebo for reducing propofol injection pain: A systematic review and meta-analysis of randomized controlled trials

Objective: Propofol is the most commonly used intravenous anesthetic medication and is most commonly associated with post-operative pain. Several drugs are investigated to reduce post-operative pain caused by propofol injection. Ondansetron is a potent anti-emetic drug showing promising results as an analgesic. This meta-analysis aims to compare the efficacy of ondansetron to placebo and lidocaine in reducing post-operative pain caused by propofol injection. Methods: PubMed, Embase, Cochrane Library, Web of Science, and Scopus were searched for relevant randomized controlled trials (RCTs) till May 2022. We conducted a meta-analysis using RevMan software version 5.4, and we assessed the quality of included RCTs using the Cochrane risk of bias tool. Results: In our study, we included 23 RCTs with 2957 participants. Compared to placebo, ondansetron significantly increased the rate of no pain [risk ratio (RR)=2.36, 95% confidence interval (CI) (1.39-4.01)], and reduced moderate [RR=0.39, 95% CI (0.30-0.52)] and severe pain [RR=0.34, 95% CI (0.24-0.50)]. Furthermore, ondansetron significantly reduced PONV [RR=0.73, 95% CI (0.58, 0.91)]. On the other hand, ondansetron showed an inferior efficacy to lidocaine regarding the incidence of no, moderate, and severe pain. Conclusion: Ondansetron is effective in reducing post-operative propofol-induced pain. However, lidocaine is more effective than it.