A Systematic Review and Meta-Analysis: Lactobacillus acidophilus for Treating Acute Gastroenteritis in Children

Systematic review and meta-analysis of 15 randomized controlled trials including 1,765 children with acute gastroenteritis. Participants were under 18 years of age, studied in single-center trials across multiple countries in Asia, Europe, and America.

Lactobacillus acidophilus was given as an oral probiotic added to standard rehydration therapy, compared with placebo or no probiotic treatment. Most trials used daily doses in the 10^9 to 10^10 CFU range, with intervention durations of 2 to 7 days or unspecified; a few trials also included zinc supplementation.

Overall, Lactobacillus acidophilus was associated with a shorter duration of diarrhea in children with acute gastroenteritis. The pooled effect for diarrhea duration was MD -0.69 days, 95% CI -1.04 to -0.33 across 15 RCTs, but heterogeneity was substantial (I2 = 94%). Benefit appeared greater when Lactobacillus acidophilus was combined with other probiotic strains (MD -0.91 days, 95% CI -1.23 to -0.59) and at daily doses of at least 10^9 CFU/day; low-dose regimens <10^9 CFU were not beneficial. Diarrhea frequency was less consistently improved, with a day 3 reduction of MD -0.61 days, 95% CI -1.00 to -0.23.

Evidence quality was moderate to low, and between-study heterogeneity was very high. Trials varied in dose, duration, probiotic formulation, and reporting of outcomes, and some studies had unclear dosing or co-interventions such as zinc, limiting interpretability and generalizability.