Role of Probiotics in Gastroenteritis
The American Gastroenterological Association recommends against using probiotics for acute infectious gastroenteritis in children in the United States and Canada, despite evidence of modest benefit in other global regions. 1
Key Recommendation by Age Group
Children with Acute Infectious Gastroenteritis (North America)
Do not use probiotics in children with acute gastroenteritis in the United States and Canada, based on two high-quality multicenter randomized controlled trials showing no benefit. 1, 2
The US study tested Lactobacillus rhamnosus GG (ATCC 53103) in 943 children across 10 emergency departments and found no reduction in moderate-to-severe gastroenteritis compared to placebo. 1
The Canadian study used a combination of L. rhamnosus R0011 and L. helveticus R0052 in 827 children across 6 emergency departments with similarly negative results. 1
Critical caveat: These North American findings directly contradict older studies from India, Italy, Poland, Turkey, and Pakistan that showed probiotics reduced diarrhea duration by approximately 22-29 hours. 1, 2 The difference likely reflects variations in host genetics, diet, sanitation, and causative enteropathogens between regions. 1
Children with Acute Infectious Gastroenteritis (Outside North America)
Consider using Saccharomyces boulardii or Lactobacillus rhamnosus GG as adjunct therapy, which may reduce diarrhea duration by approximately 24-29 hours. 2, 3
The European Society for Paediatric Gastroenterology recommends Lactobacillus reuteri (DSM 17938) as adjunct treatment in these regions. 2
Treatment duration is typically 5 days. 2
Adults with Acute Infectious Gastroenteritis
Evidence is insufficient to make a firm recommendation for or against probiotic use in adults with acute gastroenteritis. 4
A 2023 meta-analysis found no significant protective effects of probiotics in adults with gastroenteritis, with homogeneous studies showing minimal variance (I² = 6%). 4
Alternative Indications Where Probiotics ARE Recommended
Antibiotic-Associated Diarrhea Prevention
Use Lactobacillus rhamnosus GG or Saccharomyces boulardii to prevent antibiotic-associated diarrhea in both children and adults, reducing risk by approximately 50%. 2, 3
This represents moderate to high quality evidence, unlike the acute gastroenteritis data. 2
Preterm/Low Birth Weight Infants (NEC Prevention)
Use combination probiotics containing Lactobacillus spp. + Bifidobacterium spp., or single-strain B. animalis subsp. lactis, L. reuteri, or L. rhamnosus to prevent necrotizing enterocolitis in preterm infants <37 weeks gestational age. 1, 2
This recommendation is based on moderate to high quality evidence showing reduced mortality and NEC incidence. 1
Practical Dosing Considerations
When probiotics are used (in appropriate contexts), optimal dosing is ≥10¹⁰ CFU/day for maximum effectiveness. 2
For acute conditions, treatment duration is typically 5 days. 2
For chronic conditions like irritable bowel syndrome, do not exceed 12 weeks; discontinue if no improvement is observed. 5, 2, 6
Safety Considerations
Exercise caution in immunocompromised patients, premature neonates with central venous catheters, critically ill patients, those with cardiac valvular disease, and short-gut syndrome. 2
Adverse event rates in clinical trials are similar between probiotic and placebo groups, suggesting good overall safety in appropriate populations. 5
Clinical Algorithm
- Identify the clinical scenario: acute gastroenteritis vs. antibiotic-associated diarrhea vs. NEC prevention
- Determine geographic location: North America vs. other regions (for pediatric gastroenteritis)
- For acute gastroenteritis in North American children: Do not prescribe probiotics 1
- For antibiotic-associated diarrhea prevention: Prescribe L. rhamnosus GG or S. boulardii 2
- For preterm infants: Use specified combination or single-strain probiotics 1