Probiotic treatment for adults with IBS-D

Efficacy and Safety of a Probiotic Formulation in Adults With Irritable Bowel Syndrome With Diarrhea (IBS-D): A Multicenter, Randomized, Prospective, Placebo-Controlled, Double-Blind, Phase IV Clinical Study

PHASE4 · Lallemand Health Solutions · NCT05509725

This study tests whether a new probiotic can help adults with IBS-D feel better by reducing their stomach issues and improving their overall quality of life.

Quick facts

PhasePHASE4
Study typeInterventional
Enrollment162 (estimated)
Ages18 Years to 75 Years
SexAll
SponsorLallemand Health Solutions (industry)
Locations1 site (İzmir)
Trial IDNCT05509725 on ClinicalTrials.gov

What this trial studies

This study evaluates the safety and efficacy of a probiotic formulation in adults diagnosed with Irritable Bowel Syndrome with Diarrhea (IBS-D). Participants will be monitored for improvements in gastrointestinal symptoms such as abdominal pain and abnormal defecation, as well as comorbid mood disorders like anxiety and depression. The study will also assess the overall quality of life of participants over the course of the intervention. A placebo group will be included for comparison to determine the effectiveness of the probiotic treatment.

Who should consider this trial

Good fit: Ideal candidates are adults experiencing symptoms of IBS-D who meet the Rome IV criteria for diagnosis.

Not a fit: Patients with a history of inflammatory gastrointestinal diseases or severe psychiatric conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly alleviate symptoms of IBS-D and improve the quality of life for affected patients.

How similar studies have performed: Previous studies have shown promising results with probiotic treatments for IBS-D, indicating potential for success in this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Experiencing symptoms of IBS-D
* Having a diagnosis of IBS-D based on Rome IV criteria
* Participants with symptom onset at least 6 months before diagnosis
* Having a normal colonoscopy result in their medical file

Exclusion Criteria:

* A history of inflammatory or immune-mediated gastrointestinal diseases
* Diagnosed with a co-existing organic gastrointestinal disease which can affect the study
* Currently undergoing a treatment for other severe conditions such as coronary disease, neurological disorder, kidney or liver disease,
* Currently diagnosed with an eating disorder,
* Having undergone any abdominal surgery including cholecystectomy, with the exception of hernia repair or appendectomy
* Currently diagnosed with any mood- or anxiety-related disorder, major psychiatric illness, or participants with a history of suicidal ideation, or current suicidal ideation,
* Regular use of anti-diarrhea medications and laxatives however occasional use is permitted (≤ than once a month); if current use is \> once per month a one month wash out is needed,
* Unwilling to avoid the use of antidiarrheal or laxative medication on an "as-needed basis" during the full length of the study,
* Pregnant, breast-feeding or planning on becoming pregnant.

Where this trial is running

İzmir

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: IBS - Irritable Bowel Syndrome, IBS-D, Probiotics

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.