Research project led by Bailey Hanna, MS, RDN - no affiliate links, ads or sponsored products.
Five studies were initially identified that explored the effects of LGG (Lactobacillus rhamnosus GG) in IBS populations. (1,2,3,4,5) However, three of these studies were disqualified from consideration due to significant confounding factors that limited the reliability of their results. (1,2,3)
Studies Included in our Evaluation
This leaves us with two studies that avoided major confounding factors and included IBS participants:
Key Takeaways:
The evidence supporting the use of LGG for abdominal pain in IBS is limited to two clinical trials, which collectively involved 117 children with IBS. While the data suggests moderate potential benefits in reducing abdominal pain frequency, intensity, and pain resolution, these findings are preliminary. Further research with larger, well-designed studies would help to confirm these benefits.
Dosing Instructions:
Trial Duration
References
Evaluate products based on whether they transparently disclose all ingredients and their amounts, exclusively use probiotics tested in randomized placebo-controlled trials in IBS populations, and contain studied doses.
This probiotic has higher quality studies in IBS populations supporting it. View our evidence evaluation framework to learn how we assess the quality of studies.
Add condition
A randomized double-blind placebo-controlled trial of Lactobacillus GG for abdominal pain disorders in children
Aliment Pharmacol Ther 2007;25(2):177–84
CHILDREN
A randomized controlled trial of Lactobacillus GG in children with functional abdominal pain
Pediatrics 2010;126(6):e1445–52
No data
Among the IBS participants, there was a near significant reduction in the frequency of abdominal pain in the LGG group compared to the placebo group (Cohen’s d = 0.62, p = 0.067), though there was no significant difference in pain severity.
Treatment success, defined as “no pain,” was reported by 33% of the IBS LGG group versus 5% in the placebo group (p=0.029; Cohen’s h= 0.77).
However, these results should be interpreted cautiously due to wide confidence intervals and the lack of baseline severity and frequency data specifically for the IBS participants.
At weeks 5-12, 79% of the IBS LGG group achieved treatment success for the number of pain episodes, compared to 45% in the placebo group (p=0.004; Cohen’s d= 0.69). At the 13-20 week follow-up, this increased to 82% for the LGG group and 50% for placebo (p=0.001; Cohen’s h= 0.79). While the intensity of pain episodes did not show significant improvement during weeks 5-12 (p=0.1), by weeks 13-20, 72% of the IBS LGG group reported treatment success for pain intensity, compared to 46% in the placebo group (p=0.029; Cohen’s d = 0.51).
Treatment success was defined as a decrease of at least 50% in the number of episodes and intensity of pain.
The intestinal permeability test (IPT) in children from the control group showed a mean Lactulose/Mannitol ratio (La/Ma) of 0.028 (± 0.008), with a 95% confidence interval ranging from 0.025 to 0.034. Based on these results, the normal cutoff value was set at a La/Ma of less than 0.034.
At week 12, treatment with the probiotic Lactobacillus rhamnosus GG (LGG) resulted in a statistically significant decrease in the number of children with altered intestinal permeability (40% in the LGG group compared to 21% in the placebo group, with a P value of <.03). Additionally, the mean La/Ma decreased significantly in the LGG group (0.030 [± 0.005]) compared to the placebo group (0.039 [± 0.011]), with a P value of <.02.
The probiotic’s effect was most notable in children with IBS rather than those with functional abdominal pain. However, it’s important to mention that the clinical significance of this change in the La/Ma ratio remains unclear.