Using probiotics to treat Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

The Use of Directed Probiotics in ME/CFS: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

PHASE2 · Nova Southeastern University · NCT06211062

This study is testing if a new probiotic can help people aged 45 to 70 with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and possibly irritable bowel syndrome feel better.

Quick facts

PhasePHASE2
Study typeInterventional
Enrollment100 (estimated)
Ages45 Years to 70 Years
SexAll
SponsorNova Southeastern University (other)
Locations1 site (Fort Lauderdale, Florida)
Trial IDNCT06211062 on ClinicalTrials.gov

What this trial studies

This clinical study evaluates the effectiveness of the i3.1 probiotic in participants aged 45 to 70 who meet the criteria for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and may also have irritable bowel syndrome (IBS). The study is a randomized, placebo-controlled trial involving 100 participants, with half having co-morbid IBS. Participants will receive either the i3.1 probiotic or a placebo and will be assessed at baseline, eight weeks, and twelve weeks post-treatment to measure gastrointestinal inflammation and IBS severity.

Who should consider this trial

Good fit: Ideal candidates are adults aged 45 to 70 who meet the ME/CFS criteria and may have IBS.

Not a fit: Patients with recent use of probiotics or antibiotics, or those with certain gastrointestinal or severe medical conditions, may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a new therapeutic option for managing symptoms of ME/CFS and IBS.

How similar studies have performed: While the use of probiotics in gastrointestinal conditions has been explored, this specific application in ME/CFS is relatively novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria: eligible if all of the following apply:

* Meets IOM ME/CFS case definition criteria,
* Co-morbid IBS: meets RomeIV criteria for alternating or diarrhea-predominant IBS as reported during screening (technically diagnosed by a physician),
* Able to provide consent to study,
* Patients of childbearing potential must practice effective contraception during the study and be willing to continue contraception for at least six months after the intervention,
* agrees to participate in online surveys and follow-up visits.

Exclusion Criteria: ineligible if any of the following apply:

* Probiotics in the past eight weeks,
* Antibiotics in the past eight weeks,
* Pregnancy or lactating women,
* Medical conditions including short bowel syndrome, celiac disease, biliary disease, pancreatitis, inflammatory bowel disease (Crohn's disease, ulcerative colitis), severe cardiovascular, neurological condition, or liver failure,
* Gastrointestinal surgery within six months of study entry,
* History of psychiatric disorder, alcohol or illicit drug abuse.

Where this trial is running

Fort Lauderdale, Florida

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: ME/CFS, IBS - Irritable Bowel Syndrome

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.