Evidence from controlled trials and pooled data offer support for the use of probiotics to treat acute diarrhea in children and have resulted in its recommendation by some professional societies. However, much of the evidence supporting this recommendation is limited because of methodologic problems, small sample sizes, and other problems.
Recent data published in November 2018 from two high-quality, sufficiently powered, randomized controlled trials provide evidence from the largest trials to date on the benefit of probiotics in this setting. In total, the two studies enrolled 1857 infants (3-48 months) with moderate-to-severe gastroenteritis who presented to the emergency department and subsequently randomized to standard therapy (including antibiotics if indicated) plus a 5-day course of probiotics or placebo.
Neither study showed any benefit to the addition of probiotics as measured by the primary outcome of the study, which assessed the differences in clinical severity of gastroenteritis after 14 days of treatment. Along with no significant difference between the two groups in clinical severity of disease, the studies did not find a difference between the two groups in duration of diarrhea and vomiting, number of unscheduled clinic visits, nor duration of absenteeism from day care.
Notably, both studies only looked at one probiotic (Lactobacillus rhammosus), with one study using a combination of L. rhammosus and L. helveticus. Other probiotics not tested may offer different outcomes, but high-quality clinical trials such as these two recent trials are needed to test these.
Schnadower D, Tarr PI, Casper C, et al. Lactobacillus rhamnosus GG versus Placebo for Acute Gastroenteritis in Children. N Engl J Med 2018;379:2002-2014.
Freedman SB, Williamson-Urquhart S, Farion KJ, et al. Multicenter Trial of Combination Probiotic for Children with Gastroenteritis. N Engl J Med 2018;379:2015-2026.
LaMont JT. Probiotics for Children With Gastroenteritis. N Engl J Med 2018;379:2076-2077.