Adjunctive Synbiotic Therapy for <i>Helicobacter pylori</i> Eradication: An Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Abstract

Synbiotics may improve the effectiveness of antibiotic-based <i>Helicobacter pylori</i> eradication therapy; however, the available evidence remains limited. This systematic review and meta-analysis updated the evidence on the efficacy and safety of adjunctive synbiotics for <i>H. pylori</i> eradication and treatment-related adverse events. This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines and was registered in PROSPERO (CRD420251236314). PubMed, Scopus, Embase, MEDLINE, Web of Science, and Google Scholar were searched from inception to their respective final search dates in November and December 2025 for randomized controlled trials comparing antibiotic-based eradication therapy plus a synbiotic with the corresponding regimen without synbiotics. Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled for intention-to-treat (ITT), per-protocol (PP), and safety outcomes. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool, and certainty of evidence was evaluated using the GRADE approach. Six randomized controlled trials enrolling 486 participants were included; 446 participants contributed to the ITT analysis and 416 to the PP analysis. One trial was judged to be at high risk of bias, whereas five raised some concerns. The ITT analysis demonstrated improved eradication with adjunctive synbiotics (RR 1.18, 95% CI 1.04-1.34; <i>I</i>² = 44.53%). No significant benefit was observed in the PP analysis (RR 1.06, 95% CI 0.95-1.18; <i>I</i>² = 48.40%). Safety data were available from three pediatric trials (<i>n</i> = 230), with low-certainty evidence suggesting fewer overall adverse events (RR 0.27, 95% CI 0.16-0.45). Adjunctive synbiotics may modestly improve <i>H. pylori</i> eradication and may reduce overall adverse events. However, the eradication benefit was not confirmed in PP analyses, and the safety findings should be interpreted cautiously given the limited pediatric evidence.