Lactobacillus rhamnosus GG for Irritable Bowel Syndrome (IBS)
BSeveral RCTs show improvement in IBS symptoms, particularly bloating and abdominal pain. Effect strongest in IBS-D subtype. Results not uniform across all IBS subtypes.
The Bottom Line
Several RCTs show improvement in IBS symptoms, particularly bloating and abdominal pain. Effect strongest in IBS-D subtype. Results not uniform across all IBS subtypes.
Key Study Findings
Population: patients with IBS from 32 RCTs evaluating 10 probiotic strains
Population: IBS patients
Population: Children with FAPD or functional constipation
Population: Children with IBS
Population: Various populations (probiotic claims review)
Population: IBD patients
Key Statistics
8
Studies
1200
Participants
Positive
Grade
Referenced Papers
Dosage & Usage
mg = milligrams · mcg = micrograms (1,000× smaller) · IU = International Units
Commonly Used Dosages
- general:
- 10-20 billion CFU/day
- ibssupport:
- 10 billion CFU/day for 4-8 weeks
- aadprevention:
- 10-20 billion CFU/day (start with antibiotic, continue 7 days after)
Upper limit: Generally well-tolerated up to 40 billion CFU/day in clinical trials
Dosages Studied in Research
| Dosage | Duration | Effect | N |
|---|---|---|---|
| None | -- | Positive | -- |
| None | 3 weeks | Positive | -- |
| None | -- | Mixed | 3 |
| various probiotic strains | -- | Mixed | -- |
| None | -- | Mixed | -- |
| None | -- | Mixed | -- |
| None | -- | Mixed | -- |
| None | 26.0 weeks | Mixed | -- |
Best taken: On an empty stomach or 30 minutes before meals for optimal survival
Safety & Side Effects
Reported Side Effects
- ⚠ Mild gas and bloating during initial use (usually resolves in 1-2 weeks)
- ⚠ Rare reports of bacteremia in severely immunocompromised individuals
- ⚠ Occasional loose stools during adjustment period
- ⚠ Very rare: systemic infection in critically ill patients with central venous catheters
Known Interactions
- ● Antibiotics (may reduce probiotic viability; space dosing 2 hours apart)
- ● Immunosuppressants (theoretical risk of infection in immunocompromised patients)
- ● Antifungals (no known interaction but may affect gut flora balance)
Tolerable upper intake: Generally well-tolerated up to 40 billion CFU/day in clinical trials
Always consult your healthcare provider before starting any supplement.
Frequently Asked Questions
Does Lactobacillus rhamnosus GG help with Irritable Bowel Syndrome (IBS)?
How much Lactobacillus rhamnosus GG should I take for Irritable Bowel Syndrome (IBS)?
Are there side effects of Lactobacillus rhamnosus GG?
How strong is the evidence for Lactobacillus rhamnosus GG and Irritable Bowel Syndrome (IBS)?
Related Evidence
Other ingredients for Irritable Bowel Syndrome (IBS)
Lactobacillus rhamnosus GG for other conditions
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products and information on this website are not intended to diagnose, treat, cure, or prevent any disease. The evidence grades presented are based on our analysis of published peer-reviewed research and do not constitute medical advice. Always consult your healthcare provider before starting any supplement regimen.