Efficacy of Glutamine Supplementation in Patients Suffering From Irritable Bowel Syndrome With Impaired Intestinal Permeability

Inclusion Criteria:

• Adult aged 18 to 75
• Diarrheal irritable bowel syndrome (IBS-D), according to the Rome IV criteria (appendix 2)
• Francis score > 175/500 at inclusion (corresponding to moderate to severe IBS)
• Treatments for IBS stable for >1 month
• Affiliation to a social security system
• Adult person having read and understood the information letter and signed the consentform
• Woman of childbearing age having effective/very effective contraception (Cf. CTFG) (estrogen-progestins or intrauterine device or tubal ligation) for 1 month and anegative urine pregnancy test
• Postmenopausal woman: confirmatory diagnosis (amenorrhea not medically induced for atleast 12 months before the inclusion visit or biologically documented)

Exclusion Criteria:

• Taking probiotics, anti-inflammatories, corticosteroids or antibiotics systemically (oral or injectable) in the month preceding the study and during the duration of thestudy treatment,
• Known diagnosis of active autoimmune disease (type 1 diabetes, lupus, multiplesclerosis, thyroiditis, ankylosing spondylitis, rheumatoid arthritis or psoriasis)
• Known allergy to glutamine,
• Contraindication to taking glutamine, protein powder, lactulose or mannitol (includingsugar-free chewing gum),
• Use of osmotic laxatives and/or taking lactulose and/or protein supplementation (including taking glutamine) in the 4 weeks preceding the start of the study,
• Renal insufficiency (GFR<40mL/min), hepatic insufficiency (PT<70) or known heartdisease,
• ATCD of digestive disease (celiac disease, chronic inflammatory bowel disease,abdominal surgery other than appendectomy or cholecystectomy),
• Occlusive or subocclusive syndrome,
• Digestive perforation or suspicion of perforation,
• Abdominal pain syndrome of undetermined cause,
• Chronic alcohol consumption (>14 units/week),
• Pregnant or parturient or breastfeeding woman or proven absence of contraception,
• Person deprived of liberty by an administrative or judicial decision or person placedunder judicial protection/under guardianship or curatorship,
• Person participating in research participating in another trial / having participatedin another trial within 2 weeks,
• History of illness or psychological or sensory abnormality likely to prevent thesubject from fully understanding the conditions required for participation in theprotocol or preventing them from giving informed consent.