This post attempts to summarize studies  for IBS. I have often posted on CFS with IBS – this is a post looking at pure IBS. The goal is to update readers to the state of science for treating IBS and to discourage the use of folk-tales and stale medical data. Most MDs do not have time to keep current.

A good start point are these summaries:

A Review of Microbiota and Irritable Bowel Syndrome: Future in Therapies[2018].

• ” the lack of highly predictive diagnostic biomarkers and the complexity and heterogeneity of IBS patients make management difficult and unsatisfactory in many cases, reducing patient health-related quality of life and increasing the sanitary burden. “
• “because bifidobacteria concentrations have been found to be reduced in IBS compared with healthy controls, it seems reasonable, logical and safe to use prebiotics to enhance the growth of bifidobacteria and other beneficial bacteria to improve symptoms in these patients. However, based on available evidence, general use cannot be recommended in patients with IBS [18, 77].
•  Very recent meta-analyses found Saccharomyces cerevisiae CNCM I-3856GI modestly effective in decreasing IBS symptoms in adults only during supplementation [96].
• ” More studies are necessary to understand the effects of low-FODMAP diet in IBS patients.”

Clinical Practice Guidelines for Irritable Bowel Syndrome in Korea, 2017 Revised Edition

• “Five randomized placebo-controlled trials reported that probiotics (Lactobacillus rhamnosus, Lactobacillus plantarum, and VSL#3, which contains a mixture of lactobacilli, bifidobacteria, and a Streptococcus strain) improved some symptoms, mainly bloating and flatulence.^100–104“
• A probiotic mixture (Lactobacillus acidophilus, L. plantarum, L. rhamnosus, Bifidobacterium breve, Bifidobacterium lactis, Bifidobacterium longum, and Streptococcus thermophiles) provided adequate relief of overall IBS symptoms and improved stool consistency in IBS-D patients but had no significant effect on individual symptoms
• There was only ONE item with a strong recommendation: Antispasmodics 
  • Peppermint oil was cited for controlling abdominal pain.

SYMPOSIUM REPORT: An Evidence-Based Approach to IBS and CIC: Applying New Advances to Daily Practice: A Review of an Adjunct Clinical Symposium of the American College of Gastroenterology Meeting October 16, 2016 • Las Vegas, Nevada.

• Strong evidence for:
  • Eluxadoline is superior to placebo for the treatment of IBS-D^e
  • Rifaximin is effective in reducing total IBS symptoms and bloating in IBS-D
  • Lubiprostone is superior to placebo for the treatment of IBS-C
  • Linaclotide is superior to placebo for the treatment of IBS-C
  • Some fiber supplements increase stool frequency in patients with CIC
• “Symptoms associated with viscerosensory perception (abdominal pain/discomfort, bloating, pain at evacuation, and urgency) were more responsive to peppermint oil than motility-related symptoms (constipation, diarrhea, and passage of gas or mucus; “
• “these conclusions do not indicate that probiotics are not effective in individual patients, but rather that the evidence supporting their efficacy is weak.”

IBS Probiotics

See this earlier 2016 post for earlier studies – new studies are shown.

• Prescript Assist – multiple species
• Symbioflor 2 – E.Coli Probiotic
• Mutaflor — E.Coli Nissle 1917
  • Escherichia coli Nissle 1917 restores epithelial permeability alterations induced by irritable bowel syndrome mediators [2018].
• Align – Bifidobacterium infantis 35624
• Florasan B (Bifidobacterium bifidum, Bifidobacterium longum, Bifidobacterium infantis, Lactobacillus rhamnosus) – mixture
  • NOTE: Bifidobacterium infantis, B. breve and B. bifidum is increased by Human Milk Oligosaccharides

Clostridium butyricum probiotics

• ” In conclusion, CB improves overall symptoms, quality of life and stool frequency in IBS-D patients and is considered to be used as a probiotics in treating IBS-D clinically.” [2018]
• Clostridium butyricum regulates visceral hypersensitivity of irritable bowel syndrome by inhibiting colonic mucous low grade inflammation through its action on NLRP6. [2018]
• “The metabolic profile of IBS mice is significantly altered compared to control mice. Supplementation with C. butyricum to IBS mice may provide a considerable benefit by modulating host metabolism.” [2018]

Non-Prescription Substances

• Peppermint oil
• Triphala (TLP):
  • “It has also been shown that the long-term (45 days) treatment with TLP improved the number, frequency and consistency of stools excreted per day and decreased the abdominal pain and bloating in healthy patients vs. control individuals who did not receive TLP [86]. No side effects in the treated group were reported ” [2018]