Saccharomyces boulardii for the prevention of antibiotic-associated diarrhea in adult hospitalized patients: a single-center, randomized, double-blind, placebo-controlled trial.

OBJECTIVES: Antibiotic-associated diarrhea (AAD) and Clostridium difficile-associated diarrhea (CDAD) are common complications of antibiotic use. Probiotics were effective in preventing AAD and CDAD in several randomized controlled trials. This study was aimed at testing the effect of Saccharomyces boulardii on the occurrence of AAD and CDAD in hospitalized patients. METHODS: A single-center, randomized, double-blind, placebo-controlled, parallel-group trial was performed. Patients being prescribed antibiotics or on antibiotic therapy for <48 h were eligible. Exclusion criteria were ongoing diarrhea, recent assumption of probiotics, lack of informed consent, inability to ingest capsules, and severe pancreatitis. Patients received a capsule containing S. boulardii or an indistinguishable placebo twice daily within 48 h of beginning antibiotic therapy, continued treatment for 7 days after antibiotic withdrawal, and were followed for 12 weeks after ending antibiotic treatment. RESULTS: Of 562 consecutive eligible patients, 275 patients aged 79.2 ± 9.8 years (134 on placebo) were randomized and 204 aged 78.4 ± 10.0 years (98 on placebo) completed the follow-up. AAD developed in 13.3% (13/98) of the patients receiving placebo and in 15.1% (16/106) of those receiving S. boulardii (odds ratio for S. boulardii vs. placebo, 1.16; 95% confidence interval (CI), 0.53-2.56). Five cases of CDAD occurred, 2 in the placebo group (2.0%) and 3 in the probiotic group (2.8%; odds ratio for S. boulardii vs. placebo, 1.40; 95% CI, 0.23-8.55). There was no difference in mortality rates (12.7% vs. 15.6%, P=0.60). CONCLUSIONS: In elderly hospitalized patients, S. boulardii was not effective in preventing the development of AAD.