Salari, P., Nikfar, S., & Abdollahi, M. (2012). A meta-analysis and systematic review on the effect of probiotics in acute diarrhea. Inflammation & Allergy Drug Targets, 11(1), 3–14.
To clarify the efficacy of probiotics in children and adults
The effect size for probiotics compared to placebo in 19 trials related to duration of diarrhea was -0.67 (95% confidence interval [CI] = -0.95–0.38) in favor of probiotics. Heterogeneity was statistically significant. Findings included evaluation of duration of diarrhea, hours of fever, duration of hospitalization, duration of vomiting, and number of stools per day. Authors reviewed subsets of information for children, adults, cases of amebiasis and clostridium difficile, HIV, and radiation or chemotherapy.
Taken as a whole, authors concluded insufficient evidence exists for the efficacy of probiotics for different types of diarrhea in children or adults.
These findings did not provide strong support for the use of probiotics for prevention or management of diarrhea in patients receiving radiation or chemotherapy. Overall evidence in all groups was limited by a number of factors. The specific type, dosages, and timing of probiotic use varied.