Repair and pain
Does it fix a gut problem?
Inflammatory bowel disease and ulcers have real trials. Most of what gets sold as gut healing does not.
2,413
people in trials
18
human studies
1
compounds, animal or cell only
2
trials found nothing
Measured in people
Ranked by how many people, which is a fact about the evidence and not a judgement about the compound. The one at the top is the most studied, which is not the same as the best. Counts are never added across compounds, because the same person can appear in more than one trial.
- 1,337 people2 human studies
Double-blind placebo-controlled phase 3, 1337 adults meeting modified Rome III criteria randomised to plecanatide 3 mg (n equal to 443), 6 mg (n equal to 449) or placebo (n equal to 445). Durable overall complete spontaneous bowel movement responders: 20.1 percent on 3 mg, 20.0 percent on 6 mg, 12.8 percent on placebo, P equal to 0.004 for each dose. Diarrhoea 3.2 percent, 4.5 percent and 1.3 percent respectively. Four of the five authors were employees and stockholders of the sponsor, Synergy Pharmaceuticals, which the paper discloses.
Therapeutic Advances in Gastroenterology, 2017 · 1,337 people
A phase 3 randomised analysis examining whether age, sex, race and other demographic factors change the treatment response in chronic idiopathic constipation. This is the genuine randomised evidence in this compound's later literature, and it is an analysis of who responds rather than a new efficacy trial.
Clinical and Translational Gastroenterology, 2023 · no headcount in the line
- 184 people1 human study1 found nothing
found nothing184 patients on a gluten challenge: 1 mg larazotide limited gluten-induced symptoms and blunted the rise in anti-tTG antibodies, but intestinal permeability (LAMA ratio) did not differ from placebo.
Alimentary Pharmacology and Therapeutics, 2013 · 184 people
- 117 people1 human study
Phase 2 RCT in 117 surgical patients (NCT00672074): IV ipamorelin was well tolerated but did not significantly shorten time to first tolerated meal versus placebo (25.3 vs 32.6 h, p=0.15).
International Journal of Colorectal Disease, 2014 · 117 people
- 117 people1 human study
Phase 2 randomised controlled trial in 117 surgical patients. Intravenous ipamorelin was well tolerated but did not significantly shorten time to a first tolerated meal against placebo, 25.3 hours versus 32.6 hours, P equal to 0.15. This is the entire published human record for the ipamorelin half of the blend, and it is a null result on a different question.
International Journal of Colorectal Disease, 2014 · 117 people
- 117 people1 human study
117 adults undergoing small and large bowel resection were randomised to intravenous ipamorelin 0.03 mg/kg twice daily or placebo, from postoperative day 1 to day 7 or discharge, with time to tolerating a standardised solid meal as the key efficacy endpoint. This is the only randomised controlled trial of ipamorelin in people, and it is a post-surgical setting rather than any of the uses the peptide is sold for.
International Journal of Colorectal Disease, 2014 · 117 people
- 117 people1 human study
117 bowel resection patients randomised to intravenous ipamorelin or placebo twice daily. Safe, and the key efficacy endpoint of time to tolerating a solid meal was the measure it was tested against. This is the only randomised controlled trial of ipamorelin in people.
International Journal of Colorectal Disease, 2014 · 117 people
- 117 people1 human study
117 adults after open or laparoscopic bowel resection randomised to intravenous ipamorelin 0.03 mg/kg twice daily or placebo, with time to tolerating a standardised solid meal as the key endpoint. Safety was the main finding. It remains the only randomised controlled trial of ipamorelin in people.
International Journal of Colorectal Disease, 2014 · 117 people
- 95 people1 human study1 found nothing
found nothing95 otherwise healthy men with BMI 25.0 to 34.9, three-part partially blinded first-in-human study of single ascending doses from 0.075 to 2.4 mg, with and without liraglutide 0.6 mg. Drug-related adverse events, mainly gastrointestinal, in 39.0% of participants in parts 1 and 2 and 30.6% in part 3. Transient nausea and vomiting at higher doses. No difference in tolerability when combined with liraglutide, and post-dose paracetamol pharmacokinetics suggested additive effects on gastric emptying.
Diabetes, Obesity and Metabolism, 2025 · 95 people
- 65 people1 human study
Randomised, open-label, placebo-controlled, 65 healthy adults, 14 days. NR and NMN comparably increased circulatory NAD while plain nicotinamide did not do so chronically. Using ex vivo fermentation with human microbiota, the authors found that NR and NMN give rise to nicotinic acid, and that in whole blood ex vivo nicotinic acid is a potent NAD booster while NMN, NR and nicotinamide are not, proposing a gut-dependent mechanism through the Preiss-Handler pathway. If confirmed, this applies to any oral NMN product including this one. Ten authors are Nestle Research employees.
Nature Metabolism, 2026 · 65 people
- 65 people1 human study
Phase 2a, 65 adults with type 2 diabetes and overweight or obesity, 49 days of daily cotadutide (50 to 300 mcg) or placebo. Postprandial glucose area under the curve fell 21.5 percent against a 6.3 percent rise on placebo (P below 0.001); weight fell 3.41 percent against 0.08 percent (P equals 0.002); postprandial insulin rose and gastric emptying half-time lengthened by about two hours. Sponsor funded.
Journal of Clinical Endocrinology and Metabolism, 2020 · 65 people
- 40 people1 human study
40 healthy Chinese volunteers, single 2.5 mg dose and weekly titration to 5, 10 and 15 mg. Maximum concentration and area under the curve were linearly proportional to dose across 2.5 to 15 mg, supporting weekly dosing. Body weight change from baseline was minus 3.24, minus 6.26, minus 7.09 and minus 8.30 percent at 2.5, 5, 10 and 15 mg. Gastrointestinal events, vomiting, nausea, decreased appetite, diarrhoea and abdominal distension, were the most frequent adverse events. These weight figures are from healthy volunteers over a short dosing period, not from people with obesity.
Diabetes, Obesity and Metabolism, 2025 · 40 people
- 39 people1 human study
39 adults with functional constipation, four weeks of 12 g chicory inulin daily in a double-blind placebo-controlled crossover. Stool frequency, abdominal symptoms and constipation-related quality of life improved relative to placebo, alongside higher relative abundance of butyrate-producing Anaerostipes and Coprococcus. A carry-over effect meant the crossover was compromised, and the authors re-analysed the first period alone as a parallel trial, which supported the same conclusion.
BMC Gastroenterology, 2025 · 39 people
- 3 people1 human study
Phase 1 over 28 days and phase 2 over 12 weeks, both randomised, double-blind and placebo-controlled. Phase 1 produced dose-dependent weight loss with statistically significant reductions against placebo at all doses, plus reduced appetite and delayed gastric emptying. Phase 2 produced significantly greater mean percentage weight loss at doses of 500 mg and above at week 12. Gastrointestinal adverse events were class-consistent and dose-related. Three participants in phase 2 experienced transaminase elevations consistent with potential drug-induced liver injury, and those liver safety findings led to discontinuation of clinical development.
Obesity, 2026 · 3 people
- no headcount stated1 human study
Randomized double-blind placebo-controlled crossover in healthy obese subjects with a mean BMI of 39. Five days of native GLP-1 given before meals cut mean food intake per meal 15% and produced 0.55 kg of weight loss, with slowed gastric emptying as the probable mechanism. The native hormone does what its analogues do, just far more briefly.
British Journal of Nutrition, 2004 · no headcount in the line
- no headcount stated1 human study
PEGASUS. Phase 3, open-label, randomised, in adults with paroxysmal nocturnal haemoglobinuria and haemoglobin below 10.5 g/dL despite eculizumab. 41 to pegcetacoplan monotherapy, 39 to eculizumab. Primary endpoint, change in haemoglobin at week 16, favoured pegcetacoplan by an adjusted least-squares mean difference of 3.84 g/dL, P below 0.001. 35 of 41 (85 percent) on pegcetacoplan avoided transfusion versus 6 of 39 (15 percent). Non-inferiority was shown for change in reticulocyte count but NOT for change in lactate dehydrogenase. Injection site reactions 37 versus 3 percent and diarrhoea 22 versus 3 percent; breakthrough haemolysis 10 versus 23 percent. No meningitis in either group.
New England Journal of Medicine, 2021 · no headcount in the line
- no headcount stated1 human study
STEP 1. Mean body weight changed by 14.9% with semaglutide 2.4 mg weekly against 2.4% with placebo at week 68, an estimated treatment difference of 12.4 percentage points. 50.5% of the semaglutide group lost 15% or more of body weight against 4.9% on placebo. Nausea and diarrhoea were the most common adverse events, usually transient and mild to moderate. Semaglutide alone; no vitamin was co-administered.
New England Journal of Medicine, 2021 · no headcount in the line
What people using it report
- Constipation and reflux.
- no headcount stated1 human study
ENLIVEN phase 2b, 222 randomised and 219 treated, biopsy-confirmed NASH with F2 or F3 fibrosis, 24 weeks. Fibrosis improvement without NASH worsening: 7 percent placebo, 22 percent on 15 mg weekly, 26 percent on 30 mg weekly (p 0.009), 27 percent on 44 mg every 2 weeks (p 0.008). NASH resolution: 2 percent placebo versus 37, 23 and 26 percent. Most common adverse events nausea and diarrhoea. Funded by 89bio.
New England Journal of Medicine, 2023 · no headcount in the line
Measured in animals or cells, not yet in people
These are separated from the trials above rather than ranked against them, because they answer a different question. A result in a rat is a real result and a reason somebody ran the study; it is not a measurement of what happens in you. Where the human work is missing, the reason is usually money rather than failure, and that is set out at the bottom of this page.
- 1 preclinical study
Measured in animals or cells
Nanoparticle-delivered KPV accelerated mucosal healing and lowered TNF-alpha in a mouse colitis model.
Molecular Therapy, 2017 · animal
What people using these actually report
Uncontrolled self-reports, gathered from clinic write-ups, regulatory complaint records and public forums, and reproduced here as written. They are the best guide on this page to what people actually do, what they expect, and what goes wrong, and they cannot show that anything works, because nobody was measured against a placebo and the people who saw no effect mostly stopped posting. Both halves of that are true at once. The negative reports are kept in for the same reason.
- Constipation and reflux.
Sources: Trial adverse event tables supply the nausea and diarrhoea figures. The comparison between B12 and non-B12 preparations comes from forums including r/Semaglutide and telehealth patient communities, and is uncontrolled.
- The injuries people describe treating are tendinopathy, especially elbow, shoulder and Achilles, partial muscle tears, knee pain and post-surgical recovery, plus gut complaints such as reflux and inflammatory bowel symptoms.
Sources: FDA's July 2026 evaluation of BPC-157, which reproduces the FAERS adverse event reports through December 4, 2025, the Human Foods Program complaint records, and the marketed dosage forms and strengths; the three published clinic reports above, which are the only documented clinical practice; the 2025 HSS Journal systematic review and the 2026 American Journal of Sports Medicine and Sports Medicine reviews, which describe how athletes and clinicians are using these peptides and note that indications, dosing, frequency and duration all remain undefined; and public injury logs and question threads on peptide and bodybuilding forums including eroids, iSARMS, Ironsport and FITMISC. Reddit's r/Peptides and r/PeptideSupport could not be retrieved for this entry, so nothing above is attributed to any specific post, and no quotation is reproduced from any of these sources.
- Gastrointestinal effects dominate early reports, particularly diarrhoea and abdominal discomfort, and extended-release formulations are widely described as easier to tolerate.
Sources: Longevity forums, r/longevity and clinic write-ups. Uncontrolled self-report, included for what to expect and watch for, not as evidence of effect.
- Nausea, constipation and reflux, the same pattern as the branded product.
Sources: Trial adverse event tables for the gastrointestinal pattern. The rest from forums including r/tirzepatidecompound and telehealth patient communities, uncontrolled and self-reported.
- Constipation.
Sources: The gastrointestinal figures come from the REDEFINE 1 adverse event table. The rest comes from forums including r/Semaglutide and r/peptides, and is uncontrolled self-report from people using unverified material.
Why the trial record looks like this
A missing trial is usually a missing sponsor. Nobody runs a nine-figure programme on a molecule they cannot own, so the compounds with the thinnest human records are often the oldest and most freely available ones rather than the weakest. Taking Plecanatide as the example, because it states the problem most clearly:
Plecanatide is a useful case of a mechanistic differentiator that was never converted into clinical evidence.
The uroguanylin derivation and the pH sensitivity are real molecular facts, and the argument that they should produce a gentler, more proximal secretory effect than linaclotide is plausible. Marketing has leaned on it for years. What would settle it is a randomised trial of plecanatide against linaclotide with diarrhoea and discontinuation as endpoints, and that trial does not exist. Comparing the diarrhoea rates from separate placebo-controlled programmes is not a substitute, because the populations, definitions and eras differ.
The second thing to flag is the gap between the approved use and the way guanylate cyclase-C agonists are sometimes discussed in gut health content. This drug was approved to increase bowel movement frequency in people who meet formal criteria for chronic constipation. It was not studied for gut barrier function, for leaky gut, for microbiome effects, or for general digestive wellbeing, and it has a hard contraindication in young children.
A compound appears here only when a citation on its own page states this outcome and reports a result for it; naming it is not enough. Human, animal and cell work are counted separately and never merged. Participant counts are read from the study lines and deliberately undercount. Nothing here is advice, and nothing here is a recommendation to take or to avoid anything.