Irritable bowel syndrome

This study tests whether capsules containing freeze-dried fecal matter from healthy donors can safely reduce symptoms in adults with irritable bowel syndrome (IBS) that hasn't responded to usual treatments. 70 participants will be randomly assigned to receive either the fecal tra…

This study tests whether taking glutamine, an amino acid, for 8 weeks can improve insulin resistance and reduce irritable bowel syndrome (IBS) symptoms in obese patients. 110 participants will receive either glutamine or a protein powder placebo. Researchers will measure changes …

This study will follow about 4,000 people who have received a fecal microbiota transplant (FMT) — a procedure that transfers gut bacteria from a healthy donor to restore balance in the gut. It aims to see how well FMT works over 3 months, 1 year, and 5 years for conditions like r…

This study is testing a new stool test that measures calprotectin, a protein that signals inflammation in the gut. The goal is to see if the test can help doctors diagnose Crohn's disease or ulcerative colitis and tell them apart from irritable bowel syndrome. About 220 adults wi…

This study tests an online program called REACH for parents who have irritable bowel syndrome (IBS). The goal is to see if the program can help parents encourage healthy habits in their young children and reduce the chance of the kids developing similar stomach problems. About 46…

This Phase 2b study tests camlipixant, an experimental drug, in 420 adults with moderate-to-severe irritable bowel syndrome (IBS) with diarrhea or mixed bowel habits. Participants receive either camlipixant or a placebo for 26 weeks. The main goal is to see if the drug reduces we…

This study tests whether pregabalin, a drug used for nerve pain, can ease symptoms of irritable bowel syndrome (IBS). About 258 adults with mild-to-moderate IBS will receive either pregabalin or standard IBS treatments for 12 weeks. Researchers will measure changes in IBS severit…

This study tests a 9-week phone-based program called WISH that teaches positive psychology exercises to people with irritable bowel syndrome (IBS). The goal is to see if the program is practical and helpful for improving symptoms. Researchers will compare it to an educational con…

This study tests whether adding a probiotic called Ecologic Barrier to standard treatment helps adults with irritable bowel syndrome (IBS) who also have stomach issues and anxiety, depression, or stress. Sixty participants will receive either standard care or standard care plus t…

This study tests whether acupuncture can reduce stomach pain in children aged 8-17 with disorders of gut-brain interaction, like irritable bowel syndrome. Half of the 96 participants will get real acupuncture, and half will get a sham (fake) treatment. Researchers will measure pa…

This study tests whether a daily probiotic supplement can reduce symptoms like belly pain and bloating in people with Irritable Bowel Syndrome (IBS). About 252 adults with IBS will take either the probiotic or a placebo for 12 weeks. Researchers will track symptom changes and col…

This study tests whether psyllium, a common fiber supplement, can reduce belly pain and bloating in children with irritable bowel syndrome (IBS) who are sensitive to fructans—a type of sugar found in foods like wheat and onions. Researchers will give 110 kids aged 12-17 either ps…

This study tests whether Gelsectan, a supplement that coats the gut, can reduce diarrhea, belly pain, and bloating in people with diarrhea-predominant irritable bowel syndrome (IBS-D). About 90 adults in Vietnam will be randomly assigned to take Gelsectan alone, Gelsectan plus a …

This study tests an injected drug called brenipatide in 342 adults with irritable bowel syndrome with constipation (IBS-C). Participants will receive either the drug or a placebo for about 35 weeks. The goal is to see if brenipatide safely reduces abdominal pain and improves bowe…

This Phase 2 study tests whether brenipatide, given as an injection under the skin, can safely reduce abdominal pain and improve stool consistency in adults with diarrhea-predominant irritable bowel syndrome (IBS-D). About 531 participants will receive either the drug or a placeb…

This study tests whether a daily enzyme supplement (FODZYME®) can reduce bloating and stomach pain in adults who often feel bloated. About 150 people will take either the enzyme or a placebo for a period, then switch, to see if the enzyme helps break down hard-to-digest carbs. Th…

This study tests whether a daily dose of Skal Pro—a mix of a friendly bacteria (Lactobacillus plantarum 299v) and a prebiotic fiber—can reduce IBS symptoms like belly pain, bloating, and irregular bowel movements. Sixty adults with IBS will receive either the supplement or a dumm…

This study tests whether repeated magnetic pulses to the brain (rTMS) can reduce abdominal pain and diarrhea in people with diarrhea-predominant irritable bowel syndrome (IBS-D). 46 adults will receive either real or sham rTMS for 20 minutes daily over 3 weeks. Researchers will a…

This study looks at how different FODMAP diets affect gut bacteria, gut barrier function, and symptoms in people with functional gastrointestinal disorders like IBS. About 60 adults will follow either a low FODMAP, gentle FODMAP, or standard dietary advice for two weeks. Research…

This study is testing whether a fecal transplant from a carefully selected donor can reduce symptoms in people with moderate to severe IBS. The donor stool has low levels of certain proteins that may trigger IBS. 43 participants will receive the transplant during a colonoscopy an…

This study compares two online treatments for Irritable Bowel Syndrome (IBS): a low-FODMAP diet program and exposure-based cognitive behavioral therapy (E-CBT). Researchers want to find out which treatment works best for different people and how they work. The study will include …

This study looks at whether regular cardiovascular exercise (like walking, jogging, or cycling) can reduce the severity of irritable bowel syndrome (IBS) symptoms in adults who currently have a sedentary lifestyle. Researchers will enroll 30 participants aged 18-60 with moderate-…

This study tests a non-invasive belt-like device (Variable Compression System) for people with moderate to severe Irritable Bowel Syndrome (IBS). Twenty participants will wear the device for at least 6 hours daily to see if it safely reduces IBS symptoms like pain, bloating, and …

This study tests whether adding the supplement N-acetylcysteine (NAC) to the antibiotic rifaximin can better relieve symptoms of irritable bowel syndrome with diarrhea (IBS-D). The idea is that NAC may break down mucus in the gut, helping rifaximin work more effectively. The tria…

This study looks at whether adding osteopathic care (a type of hands-on therapy) to a flexible low-FODMAP diet can further reduce IBS symptoms in people with fibromyalgia. About 96 adults will receive either real or sham osteopathic sessions alongside the diet. Researchers will t…

This study tests whether a small, home-use device that gently stimulates a nerve in the ear can help young adults (ages 18-29) manage pain and other symptoms of irritable bowel syndrome (IBS). Eighty participants will use either the active device or a sham (inactive) version twic…

This study tests whether Gelsectan, a capsule made from plant-based ingredients, can reduce abdominal pain and improve stool consistency in people with diarrhea-predominant irritable bowel syndrome (IBS-D). About 330 adults will take either Gelsectan or a placebo twice daily for …

This study compares two different exercise programs combined with dietary advice to see which better reduces symptoms in people who have both fibromyalgia and irritable bowel syndrome. Researchers will enroll 30 adults aged 30 to 65 with moderate to severe IBS and confirmed fibro…

This study tests whether ebastine, an allergy medication, works better than mebeverine, a common IBS drug, for reducing belly pain and improving daily life. About 200 adults with non-constipated IBS will take one of the two pills for 12 weeks. The goal is to see if ebastine provi…

This study compares the DOMINO diet app to the strict low FODMAP diet for easing irritable bowel syndrome (IBS) symptoms. About 110 adults with IBS will use either the app or follow the strict diet. The goal is to see if the app works as well as the standard diet, offering a more…

This study tests whether a daily drink mix containing special sugars (HMO-2FL) and a postbiotic can reduce stomach pain, bloating, and other IBS symptoms. About 402 adults with IBS will take either the supplement or a placebo for 6 weeks. Researchers will compare symptom scores t…

This study tests whether transplanting gut bacteria from healthy donors can relieve symptoms of irritable bowel syndrome (IBS). 102 adults who haven't responded to at least three standard treatments will receive donor bacteria either in capsules or through a tube into the nose an…

This study tests whether a dietary supplement called DIELEN Protect, which contains glutamine and marine peptides, can ease symptoms of irritable bowel syndrome (IBS). One hundred adults with moderate to severe IBS will take either the supplement or a placebo for 8 weeks. Researc…

This study tests whether taking glutamine, a natural amino acid, can reduce symptoms in people with diarrhea-predominant irritable bowel syndrome (IBS-D) who also have increased intestinal permeability (leaky gut). About 60 adults will receive either glutamine or a placebo daily …

This pilot study tests whether adding immersive virtual reality therapy to the standard IBS medication linaclotide can improve symptoms and quality of life more than medication alone. Researchers will enroll 65 adults with IBS-C and compare those getting real VR therapy to those …

This study tests whether an ancient type of wheat (Triticum monococcum) causes fewer stomach and other symptoms than modern wheat in people with non-celiac wheat sensitivity. Sixty-eight adults who follow a wheat-free diet will eat both types of wheat in a blinded crossover desig…

This study tests two digital treatments for children aged 8-17 with chronic stomach pain caused by gut-brain interaction disorders. After a 4-week online education program, participants are randomly assigned to either internet-based cognitive behavioral therapy (iCBT) or gut-dire…

This early-phase study at Mayo Clinic tests whether adding the medication mirtazapine to a low-FODMAP diet improves symptoms of irritable bowel syndrome with diarrhea (IBS-D) better than diet alone. About 20 adults aged 18-70 will take either mirtazapine or a placebo while follow…

This phase 3 trial tests whether a low FODMAP diet can improve symptoms and quality of life in people with moderate to severe irritable bowel syndrome (IBS) who do not have lactose malabsorption. Sixty participants will follow the diet with guidance from a dietitian. The goal is …

This study tests whether a daily synbiotic supplement (Vivatlac) can change the gut bacteria of people with irritable bowel syndrome (IBS). Twenty adults with moderate to severe IBS will take either the supplement or a placebo for 12 weeks. Researchers will compare stool samples …

This study tests whether a daily synbiotic (a mix of probiotics and prebiotics) can reduce IBS symptoms like belly pain, bloating, and irregular bowel habits. About 200 adults with moderate-to-severe IBS will take either the synbiotic or a placebo for 36 weeks. The goal is to see…

This study tests whether avoiding foods identified by a skin patch test can improve irritable bowel syndrome (IBS) symptoms. 250 adults with IBS will undergo patch testing for 80 foods and then follow either a true avoidance diet (avoiding foods they are allergic to) or a sham di…

This study tests whether taking oral glutamine, a dietary supplement, three times a day for 12 weeks can reduce chronic stomach pain, bloating, and diarrhea in veterans with Gulf War Illness. Researchers will also check if it helps repair the gut lining. The trial involves 80 vet…

This study tests whether low-frequency magnetic stimulation to a brain area linked to pain can reduce chronic visceral pain in people with irritable bowel syndrome with diarrhea (IBS-D). 42 adults will receive either real or sham stimulation daily for two weeks. The goal is to se…

This study tests whether a probiotic called Saccharomyces boulardii can reduce symptoms of irritable bowel syndrome (IBS) in adults. About 406 people with non-constipated IBS will take either the probiotic or a placebo daily for 8 weeks. Researchers will measure changes in sympto…

This study at Mayo Clinic tests whether biofeedback therapy and inspiratory muscle training can help people with dyssynergic defecation—a condition where pelvic floor muscles don't relax properly during bowel movements. Two hundred adults aged 18 to 80 with chronic constipation w…

This study tests whether a simple biofeedback technique—teaching people to control their abdominal and chest muscles using a video—can reduce visible bloating after meals. 100 adults with irritable bowel syndrome, dyspepsia, or functional bloating will be randomly assigned to eit…

This study compares two treatments for abdominal pain in people with irritable bowel syndrome with constipation (IBS-C): a home-use device that delivers mild electrical stimulation (TEA) and the drug escitalopram (Lexapro). About 160 participants will be randomly assigned to one …

This study is testing the drug eluxadoline (Viberzi) in children aged 6 to 17 who have irritable bowel syndrome with diarrhea (IBS-D). The goal is to see if it improves stool consistency and is safe for kids. About 95 children will take either the drug or a placebo for 4 weeks, a…

This study is testing whether a single low dose of esketamine, given during a colonoscopy, can reduce symptoms of irritable bowel syndrome (IBS) in adults who also have anxiety or depression. The trial plans to enroll 552 participants and will measure symptom severity and quality…

This study looks at whether a special low-FODMAP diet and probiotics can reduce chronic pelvic pain in women who have both endometriosis and irritable bowel syndrome (IBS). Researchers will compare three groups: one getting the diet plus a placebo, one getting the diet plus probi…

This study investigates whether a gut infection called Brachyspira causes IBS symptoms by making the immune system overreact to certain foods. Researchers will use advanced imaging to identify which foods trigger reactions in the gut. Participants will eliminate those foods for f…

This study aims to find a marker in stool or urine that can objectively measure whether people with Irritable Bowel Syndrome (IBS) are sticking to their prescribed diet. Researchers will enroll 94 adults with moderate-to-severe IBS and track their food intake and gut symptoms. Th…

This study aims to collect medical data and biological samples (blood, urine, stool, and tissue) from up to 4,000 adults with known or suspected gastrointestinal diseases. Participants receive standard medical care at the NIH, and any extra samples or leftover tissue from procedu…

This study investigates how the gut and brain communicate in people with Irritable Bowel Syndrome (IBS) who also experience anxiety or depression. Researchers will compare 100 IBS patients with anxiety or depression to 100 healthy volunteers using brain scans, stool samples, and …

This study is creating a registry of up to 5,000 patients with various gut movement disorders, such as GERD, gastroparesis, and IBS. Doctors will use standard criteria to make accurate diagnoses and collect patient-reported outcomes. The goal is to improve understanding of these …

This study looks at the gut bacteria of 100 people with irritable bowel syndrome (IBS) to see if a stool test can help diagnose the condition. Half will follow a low-FODMAP diet, a common but restrictive eating plan. Researchers will compare the bacteria and symptoms between the …

This study aims to find out how many relatives of people with celiac disease have non-celiac wheat sensitivity (NCWS) or other gut issues like IBS. Participants will follow a strict wheat-free diet for 6 weeks and report their symptoms. The goal is to better understand the link b…

This study looks at how much of the constipation medicine prucalopride passes into breast milk. Researchers will collect milk samples from 12 women over 24 hours and track their babies' growth and any side effects for one year. The goal is to understand infant exposure, not to tr…

This study looks at people with Irritable Bowel Syndrome (IBS) who have a reduced ability to break down starch and sugar due to low enzyme levels. Researchers want to see if these individuals have a smaller rise in blood sugar after a meal and more bowel symptoms compared to thos…

This observational study is looking at the gut microbiome of 315 people, including those with irritable bowel syndrome that started after an infection. Researchers will compare their gut bacteria to people who had an infection but no IBS, and to healthy controls. The goal is to f…

This study takes small tissue samples from the rectum of people with irritable bowel syndrome (IBS) and healthy volunteers to measure how the nerves in the gut are working. Researchers will use special imaging and other lab techniques to see how these nerves respond to different …

This study compares a new orally disintegrating form of Trimedat (trimebutine) to the standard tablet in 36 healthy adults. The goal is to see if the new version is absorbed similarly and is safe. This trial does not treat any disease; it only gathers data on how the drug behaves…

This study looks at how inflammation from type 2 diabetes, end-stage kidney disease, or irritable bowel syndrome affects the way the body processes drugs. Researchers will collect blood samples from 150 adults and children to measure inflammation markers and estimate how they mig…

This study is following 2000 adults with functional digestive disorders like irritable bowel syndrome, dyspepsia, and constipation. Researchers will collect medical data and biological samples (biopsies, blood, urine, stool) during routine care. The goal is to find markers that c…

This study is creating a long-term group of 600 people with irritable bowel syndrome (IBS) to track how the disease changes over time. Participants will fill out questionnaires about their symptoms, quality of life, and habits, and provide stool samples every six months. The goal…

This study is testing a new online food questionnaire to see if it can accurately measure what people eat, including FODMAPs (certain carbs that can cause digestive issues). Researchers will compare the questionnaire to a standard 4-day food diary in 400 adults, both with and wit…

This study looks at whether a simple breath test can tell if people with moderate to severe irritable bowel syndrome (IBS) will feel better on a lactose-free diet. About 90 adults with IBS will take the breath test and then follow a lactose-free diet for 4 weeks. Researchers will…

This study at Children's Hospital of Philadelphia is observing 90 children aged 8-18 with and without irritable bowel syndrome (IBS). Participants wear a wireless patch on their belly to measure gut muscle activity, record their diet, and provide stool and urine samples. The goal…

This study looks at the gut bacteria of 40 people with irritable bowel syndrome (IBS) who have constipation and produce high methane. Researchers will collect stool and blood samples to see which bacteria are present and how they change with standard treatment. The goal is to bet…

This study looks at how gut bacteria and diet affect symptoms in people with irritable bowel syndrome (IBS). Researchers will measure bile acids, short-chain fatty acids, and gut microbes in stool samples from 72 adults with IBS and healthy volunteers after a controlled diet. Par…

This study uses a smartphone app called SOMA to track daily mood, pain, and activity in 800 people with acute or chronic pain over four months. The goal is to find patterns that predict whether acute pain becomes chronic, or if chronic pain flares up. A smaller group will also ha…

This study is testing a new way to measure abdominal pain in people with Irritable Bowel Syndrome (IBS). Researchers will record heart rate, sweat, and muscle signals from a belt worn around the belly. They hope to create an objective pain index that could help doctors better und…