Combining a low-FODMAP diet with mirtazapine to treat IBS with diarrhea
Official title: Novel Pilot Study to Treat Symptoms of IBS With Diarrhea Using Combination Therapy of a Low-FODMAP Diet and a Neuromodulator
Run by Mayo Clinic · NCT06684470 · Data updated 2026-11-12
This study is testing if combining a low-FODMAP diet with the medication mirtazapine can help adults with diarrhea-predominant irritable bowel syndrome feel better and improve their quality of life.
Quick facts
| Phase | Early Phase 1 |
|---|---|
| Study type | Interventional |
| Ages | 18 Years to 70 Years |
| Sex | All |
| Enrollment | 20 (estimated) |
| Sponsor | Mayo Clinic Academic / other |
| Locations | 1 site (Jacksonville, Florida) |
| Status | Recruiting |
| Started | December 19, 2024 |
| Main results expected | December 19, 2026 |
| Study ends | December 19, 2026 |
| Registry record updated | December 18, 2025 |
| Trial ID | NCT06684470 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are adults aged 18-70 with a diagnosis of diarrhea-predominant IBS and a score greater than 175 on the IBS-SSS questionnaire.
✕Probably not a fit
Patients with prior diagnoses of celiac disease, inflammatory bowel disease, or those with ongoing significant anxiety or depression may not benefit from this study.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This research investigates the effectiveness of a combination therapy involving a low-FODMAP diet and the medication mirtazapine for treating symptoms of diarrhea-predominant irritable bowel syndrome (IBS-D). Participants will be adults aged 18-70 who meet specific criteria for IBS-D and will be evaluated for improvements in symptoms such as abdominal pain and diarrhea using validated questionnaires. The study aims to determine if the combination therapy leads to greater symptom relief and improved quality of life compared to the diet alone.
Why it matters
Potential benefit: If successful, this approach could provide a new effective treatment option for patients suffering from IBS-D.
How similar studies have gone: While the combination of a low-FODMAP diet and mirtazapine is a novel approach, similar dietary interventions have shown promise in managing IBS symptoms in other studies.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Participants must meet all of the inclusion criteria to participate in this study: * Adults (ages 18-70) * Score of \>175 on the IBS-SSS questionnaire * Must meet Rome IV criteria for IBS-D * If subject is of reproductive capability a negative urine pregnancy test must be available prior to entering the study * Ability to understand study procedures and to comply with them for the entire length of the study Exclusion Criteria: * All candidates meeting any of the below exclusion criteria at baseline will be excluded from study participation: * Score of \< 175 on the IBS-SSS * Prior diagnoses of: known celiac disease, small intestinal bacterial overgrowth, inflammatory bowel disease, or microscopic colitis * Ongoing significant anxiety or depression * A history of a known side effect to mirtazapine * Prior treatment with a low FODMAP diet or mirtazapine without clinical benefit * Active alcohol or drug abuse * Inability to read or understand the consent form * Any other medical or psychological reason that would prevent active participation in a research study * Pregnant females
Where it's running
-
Mayo Clinic
Jacksonville, Florida, United States Recruiting
Study contacts
- Principal investigator: Brian E Lacy, MD — Mayo Clinic
- Study coordinator: Jessica C Petrov, MD
- Email: Petrov.Jessica@mayo.edu
- Phone: 904-953-2000
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.