Recent Guideline
In its February 2023 Global Guideline “Probiotics and Prebiotics” for IBS, the World Gastroenterology Organization looked at the level of evidence for probiotics.
Three strains, as well as a combination of several strains, were supported by level 2 evidence, meaning at least two randomized studies with converging results. These are Bifidobacterium bifidum MIMBb75, which improves overall symptoms and quality of life; Lactobacillus plantarum 299v (DSM 9843), which acts on the severity of abdominal pain and bloating; and B infantis 35624 (new name: B longum 35624), which improves the overall assessment of IBS symptoms, as does the multistrain product containing L rhamnosus GG, L rhamnosus LC705, Propionibacterium freudenreichii ssp shermanii JS DSM 7067, and B animalis ssp lactis B012 DSM 15954.
Efficacy and Availability
Probiotics belonging to the category of dietary supplements or medical devices are not required to provide evidence for a mechanism of action or even efficacy to be marketed. Thus, for most probiotics sold, there are no human or even animal studies available.
Dr. Sabaté proposed a choice of probiotics based on the literature and the presence of at least one randomized placebo-controlled trial conducted in patients with IBS showing positive results.
“,” he emphasized. The parameters that can be improved include symptom severity, quality of life, abdominal pain, and bloating.
Effective Probiotics
B longum 35624, which was developed with researchers from University College Cork in Ireland, is probably the most studied in animals and humans. Research has encompassed the mechanistic, clinical, and safety aspects of the probiotic. It has shown good results on the IBS-Symptom Severity Score (SSS), quality of life, abdominal pain, bowel disturbances, and bloating. The treatment duration in studies is 4-8 weeks.
L plantarum 299v (DSM 9843) affects the frequency of abdominal pain and pain score. The treatment duration in studies is 4 weeks.
The multistrain product that includes L plantarum CECT 7484/L plantarum CECT 7485/ Pediococcus acidilactici CECT 7483 allows for an improvement in quality of life and anxiety related to digestive symptoms. No positive effect has been described on digestive symptoms, especially diarrhea. The treatment duration is 6 weeks.
B bifidum MIMBb75 (both normal and heat-inactivated forms) is beneficial for pain, the composite IBS-SSS score, and quality of life. The treatment duration is 4-8 weeks.
“Except for the multistrain combination, which is more suited to patients with diarrhea-predominant IBS, the other three probiotics can be prescribed regardless of the IBS subtype,” said Dr. Sabaté. “Treatment durations are typically 4 weeks, but it is possible to continue up to 8 weeks, which is the maximum duration of these studies. In practice, there are no tolerance issues with probiotics prescribed for IBS based on the literature. These should be tested under the conditions and for the duration of the published studies and should only be continued if there is individual benefit on symptoms or quality of life.”
Note that microbiota analyses conducted for individual purposes are of no help in choosing probiotics.