Irritable Bowel Syndrome and the Identification of Wheat or Gluten Sensitivity

Study Purpose

The aim of our study will be to establish in how many subjects with gastrointestinal symptoms and previous diagnosis of irritable bowel syndrome (IBS), the clinical picture is attributable to non celiac gluten sensitivity (NCGS) or fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) intolerance. For this purpose, all subjects with IBS will take a low FODMAPs diet, which implies the absence of cereals and consequently of gluten, and those presenting symptom improvement during this dietary treatment, will be exposed to a double-blind gluten or placebo challenge, to make a diagnosis of NCGS.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

Searching Both is inclusive of interventional and observational studies.

Eligible Ages 18 Years - 70 Years
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - a gluten-containing diet for at least six months before enrollment - anti-transglutaminase antibodies (IgA and IgG) absence - normal serum IgA levels - prick and specific IgE tests for wheat allergy negative

    Exclusion Criteria:

    - celiac disease - wheat allergy - chronic intestinal inflammatory diseases - psychiatric disorders - major abdominal surgery (in particular intestinal resections) - diabetes mellitus - previous anaphylactic episodes - gluten-free diet in the previous six months - pregnant or lactating women.

Trial Details

Trial ID:

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Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

University of Bari
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Michele Barone
Principal Investigator Affiliation University of Bari
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Overall Status Recruiting
Countries Italy

The disease, disorder, syndrome, illness, or injury that is being studied.

Non-celiac Gluten Sensitivity, Irritable Bowel Syndrome
Additional Details

Study design: For this study, patients with diagnosis of IBS performed by Rome IV criteria and followed as outpatients at the Clinical Nutrition Clinic of "Petrucciani" Nursing Home of Lecce (LE), Italy, will be enrolled. At baseline, the enrolled subjects will follow a balanced normal-caloric low-FODMAP and gluten-free diet for a period of 30 days. At the end of the 30 days patients who did not experience an improvement in symptoms will be considered "non-responders" and discontinue the clinical trial. Only those subjects who had showed a significant improvement in symptoms, will be enrolled for the phase 2 of the study that includes a challenge with gluten or with placebo, as described by the Salerno criteria.

Arms & Interventions


Active Comparator: patients with IBS treated with gluten

patients receiving flour with gluten (nocebo)

Placebo Comparator: patients with IBS treated with placebo

patients receiving gluten-free flour (placebo)


Dietary Supplement: - diet containing gluten

gluten-free flour (placebo) will be added for 5 days to the low FODMAP diet. After 1 week of wash-out, patients will switch to flour with gluten (nocebo) for another 5 days

Dietary Supplement: - Placebo


Contact a Trial Team

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International Sites

Michele Barone, Bari, BA, Italy




Michele Barone

Bari, BA, 70124

Site Contact

Michele Barone


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