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Probiotics for Antibiotic-Associated Diarrhea and Clostridium difficile Infection: A Review of Clinical Effectiveness

Last updated: September 20, 2018
Project Number: RC1022-000
Product Line: Rapid Response
Research Type: Drug
Report Type: Summary with Critical Appraisal
Result type: Report


  1. What is the clinical effectiveness of concurrent probiotic and antibiotic use for preventing antibiotic-associated diarrhea and C.difficile infection?
  2. What is the clinical effectiveness of probiotics for treating and managing antibiotic-associated diarrhea and C.difficile infection?

Key Message

No clear patterns have emerged regarding the impact of probiotics on preventing AAD, CDAD, and CDI. Relative to placebo, active control, or treatment, probiotics reduced the risk of AAD but there were certain conditions under which the reduction was not statistically significant. The findings on the effectiveness of probiotics at preventing CDAD were mixed. Two systematic reviews reported that probiotics were better at preventing CDAD compared to placebo or no treatment, but three other reviews did not show significant differences in effect. Similarly, the effect of probiotics on preventing infection varied across three systematic reviews and two RCTs. The relative impact of probiotics on gastrointestinal adverse events varied with the set of comparators. Probiotics did not have a significant effect when compared with placebo only, no treatment only, placebo or usual care, and placebo or no treatment. Only when intestinal distention was added to pain did probiotics show significant effect relative to no treatment. When active control was included to placebo and no treatment in the comparator arm, probiotics significantly decreased the risk of adverse events.None of the studies reported on the effectiveness of probiotics in treating AAD or CDAD, but one RCT reported that a mixture of four probiotics was only as effective as placebo at treating CDI.