Strain-Specific Efficacy of Saccharomyces boulardii CNCM I-745 in the Prevention of Antibiotic-Associated Diarrhea: A Systematic Review and Meta-Analysis

Aim: to perform a systematic review and meta-analysis of the efficacy of Saccharomyces boulardii CNCM I-745 in the prevention of antibiotic-associated diarrhea (AAD) in adults and children.

Materials and methods. The protocol for this systematic review and meta-analysis was prospectively registered in the international PROSPERO database (CRD420261296647). In accordance with the PRISMA 2020 guidelines, a systematic literature search was conducted in MEDLINE/PubMed, Embase, the Cochrane Library, Scopus, and RSCI (Russian Science Citation Index) from the time first publications appeared to February 6, 2026. Studies evaluating the efficacy of S. boulardii CNCM I-745 (Enterol^®) in the primary prevention of AAD and Clostridioides difficile infection (CDI) in adults and children were included.

Results. A total of 29 studies met the inclusion criteria and were included in the meta-analysis. The use of S. boulardii CNCM I-745 was associated with a statistically significant reduction in the incidence of AAD compared with control in the overall pooled analysis (OR 0.38; 95 % CI 0.32–0.45). Subgroup analysis confirmed the efficacy of the probiotic in both adults (20 studies, n = 3937; OR 0.45; 95 % CI 0.33–0.61) and children, in whom the effect was even more pronounced (7 studies, n = 1608; OR 0.31; 95 % CI 0.23–0.41). In the analysis of studies in which S. boulardii CNCM I-745 was used as part of Helicobacter pylori eradication regimens, a statistically significant reduction in AAD risk was also observed (13 studies, n = 2333; OR 0.36; 95 % CI 0.25–0.52). Additional analysis demonstrated a significant reduction in CDI risk with S. boulardii CNCM I-745 use (8 studies, n = 18,426; OR 0.67; 95 % CI 0.49–0.92).

Conclusions. The results of this meta-analysis demonstrate the high efficacy of S. boulardii CNCM I-745 in the prevention of AAD in adults and children, as well as in reducing the risk of CDI during antibiotic therapy from the very first

day of treatment.

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