Potential efficacy and safety of Xiyanping injection as adjuvant therapy in treatment of suppurative acute tonsillitis: a meta-analysis, trial sequential analysis, and certainty of evidence.

Antibiotic resistance has emerged as a global concern. Xiyanping injection (XYP), a traditional Chinese medicine injection, has been extensively utilized for the treatment of suppurative acute tonsillitis (SAT) in China, exhibiting clinical efficacy. Consequently, there is a need for further evaluation of the potential effectiveness and safety of this treatment. This meta-analysis consolidated data from multiple independent studies to assess the overall treatment efficacy of XYP as adjuvant therapy in patients with SAT. The search for randomized controlled trials (RCTs) encompassed databases from their inception to 1 April 2024, including the Cochrane Library, PubMed, Embase, SinoMed, CNKI, Wanfang, VIP, and CBM. Data extraction, methodological quality assessment, and meta-analysis were performed independently by two researchers. Review Manager 5.4 was used for data analysis. Various tools were employed for assessment, including forest plots to visualize results, funnel plots to detect publication bias, trial sequential analysis to estimate sample size, and GRADE to evaluate evidence quality. A comprehensive analysis of 32 RCTs involving 4,265 cases was conducted. When compared to conventional treatments (CTs; β-lactams/clindamycin hydrochloride injection/ribavirin) alone, the combination of XYP with CTs demonstrated significant reductions in symptom duration. This included sore throat (MD = -21.08, 95% CI: -24.86 to -17.29, < 0.00001), disappearance of tonsillar redness and swelling (mean difference [MD] = -20.28, 95% confidence interval [CI]: -30.05 to -10.52, < 0.0001), tonsil purulent discharge (MD = -22.40, 95% CI: -28.04 to -16.75, < 0.00001), and normalization of temperature (MD = -19.48, 95% CI: -22.49 to -16.47, < 0.00001). Furthermore, patients receiving CTs combined with XYP exhibited lower levels of interleukin-6 (MD = -7.64, 95% CI: 8.41 to -6.87, < 0.00001) and interleukin-8 (MD = -5.23, 95% CI: -5.60 to -4.86, < 0.00001) than those receiving CTs alone. Additionally, the combination therapy significantly improved the recovery rate (relative risk [RR] = 1.55, 95% CI: 1.37 to 1.77, < 0.00001), white blood cell count recovery rate (RR = 1.13, 95% CI: 1.04 to 1.23, = 0.004), and disappearance rate of tonsillar redness and swelling (RR = 0.51, 95% CI: 1.14 to 1.38, < 0.00001), with no significant increase in adverse events (RR = 0.47, 95% CI: 0.20 to 1.10, = 0.08). The current systematic review and meta-analysis tentatively suggest that the combination of XYP and CTs yields superior clinical outcomes for patients with SAT compared to CTs alone, with a favorable safety profile. Nonetheless, these findings warrant further confirmation through more rigorous RCTs, given the notable heterogeneity and publication bias observed in the included studies. https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=296118, identifier CRD42022296118.