The best peptides for gut health, judged by evidence, are FDA-approved drugs for specific conditions. Teduglutide (Gattex) helps people with short bowel syndrome cut back on IV nutrition, and linaclotide (Linzess) and plecanatide (Trulance) treat chronic constipation and IBS with constipation.[1][3][5] Popular gut peptides sold online, such as BPC-157 and KPV, rest mostly on animal studies,[8][12] and larazotide, a “leaky gut” peptide, had its phase 3 trial stopped in 2022.[14]
This guide grades each by evidence, explains what the trials found, and covers safety. For background on how peptides and gut bacteria interact, see our peptides and the gut microbiome guide, and for related compounds, the healing and recovery peptides hub.
Best peptides for gut health: evidence at a glance
| Peptide or drug | Evidence level | What was shown | FDA status | Our profile |
|---|---|---|---|---|
| Teduglutide (Gattex) | FDA-approved for this use | 63% cut IV nutrition by more than 20% vs 30% on placebo[2] | Approved for short bowel syndrome needing IV support, age 1+[1] | — |
| Linaclotide (Linzess) | FDA-approved for this use | 33.7% vs 13.9% met FDA’s IBS-C responder goal[4] | Approved for IBS-C (age 7+), chronic constipation, child constipation (age 2+)[3] | — |
| Plecanatide (Trulance) | FDA-approved for this use | About twice as many durable responders as placebo[6] | Approved for adult chronic constipation and IBS-C[5] | — |
| Icotrokinra | Human RCTs (investigational) | 55% to 63% clinical response vs 27% in ulcerative colitis[7] | Approved for psoriasis only, not colitis | — |
| Larazotide | Human RCTs (failed) | Phase 2b hit with lowest dose only; phase 3 stopped[13][14] | Not approved | — |
| BPC-157 | Animal or lab only | One 53-person enema trial, no clear benefit[8] | Not approved | BPC-157 |
| KPV | Animal or lab only | Reduced colitis in mice; no human data[11][12] | Not approved | KPV |
The approved gut peptides
Teduglutide for short bowel syndrome
Teduglutide is a lab-made version of GLP-2, a gut hormone that helps the intestinal lining grow and absorb nutrients.[1] In the 24-week STEPS trial, 86 adults with short bowel syndrome and intestinal failure took teduglutide or placebo daily. 63% on teduglutide reduced their IV nutrition volume by more than 20%, versus 30% on placebo, and more patients gained at least one day a week off IV support.[2] It is approved for adults and children 1 year and older who depend on IV nutrition.[1]
Linaclotide and plecanatide for constipation
Both drugs are small peptides that copy natural gut hormones, guanylin and uroguanylin. They act on the intestinal lining to draw fluid into the bowel.[3][5]
- Linaclotide: in a 26-week trial of 804 people with IBS with constipation, 33.7% met FDA’s combined pain-and-bowel responder goal versus 13.9% on placebo. Diarrhea led 4.5% to stop treatment.[4]
- Plecanatide: in a trial of 1,394 adults with chronic idiopathic constipation, about 20% were durable responders versus 10.2% on placebo; diarrhea affected about 6%.[6]
Both carry boxed warnings: linaclotide must not be used under age 2, and plecanatide must not be used under age 6, because of fatal dehydration in young mice.[3][5]
Icotrokinra: an oral peptide being tested in colitis
Icotrokinra, approved in 2026 for psoriasis, is now being tested in ulcerative colitis. In a 252-person phase 2b trial, clinical response at 12 weeks was 55% to 63% across three daily doses versus 27% on placebo.[7] It is not approved for colitis.
The unproven gut peptides
BPC-157
BPC-157 is described as a stable peptide from gastric juice and was developed in Croatia as a possible bowel disease drug under the code PL 14736.[9] FDA’s 2026 review found one human efficacy trial, reported only as a 2005 meeting abstract. Fifty-three people with mild-to-moderate ulcerative colitis received a BPC-157 enema or placebo for two weeks. Disease activity fell 3.2 points with BPC-157 and 1.6 with placebo, a difference that was not statistically clear, and FDA called the data inadequate. No studies tested oral or injected BPC-157 in colitis.[8] FDA advisers voted 8 to 6 in July 2026 to recommend allowing it in compounding for ulcerative colitis, but FDA has not acted.[10] Our oral vs injectable BPC-157 guide and BPC-157 clinical trials review cover more.
KPV
KPV, a tiny fragment of the hormone alpha-MSH, is absorbed by a gut transporter that increases during inflammation. In mice, KPV in drinking water reduced two kinds of chemically induced colitis.[11] FDA found no clinical studies or human exposure data for KPV.[12]
Larazotide
Larazotide was designed to block zonulin and tighten the junctions between gut cells in celiac disease. In a 342-person phase 2b trial, only the lowest dose, 0.5 mg three times daily, reduced symptoms more than placebo.[13] The phase 3 trial was terminated in 2022 after an interim analysis showed the number of extra patients needed to detect a meaningful benefit was too large.[14][15]
Why no peptide is proven for “general” gut health
Every approved gut peptide treats a defined condition, measured with clear outcomes such as IV nutrition volume or bowel movements per week. “Gut health” in marketing is broader and vaguer: bloating, irregularity, “leaky gut,” or a sense that digestion is off. Those symptoms have many causes, from food intolerances and IBS to celiac disease, medication side effects and, less often, serious disease.
That vagueness makes products hard to test and easy to sell. A peptide that calms chemically induced colitis in mice may say little about bloating in a healthy adult. Larazotide is a useful example: it targeted gut permeability directly, in a condition where permeability is well documented, and still could not show a clear benefit in a large trial.[14] If symptoms are bothering you, a diagnosis usually points to a better-proven treatment than any peptide sold online.
Safety
Approved gut peptides have known side effects, mainly diarrhea for linaclotide and plecanatide. Teduglutide’s label warns it may speed the growth of existing tumors and calls for colonoscopy after the first year and regular follow-up, plus periodic blood tests, so it is used under specialist care.[1] Peptides sold online have unchecked purity and dosing, and for KPV no human safety data exist.[12]
Questions for your clinician
- Do my symptoms point to a specific condition, such as IBS, celiac disease or inflammatory bowel disease?
- Would an approved peptide, like linaclotide or plecanatide, fit my symptoms?
- Do I need testing, such as a colonoscopy or celiac blood test, first?
- If I am considering BPC-157 or KPV, what are the risks given my medicines?
The bottom line
The best peptides for gut health are approved drugs matched to a diagnosis: teduglutide for short bowel syndrome and linaclotide or plecanatide for chronic constipation and IBS-C. BPC-157 and KPV are popular but unproven in people, and larazotide’s phase 3 failure is a reminder that early promise often fades. Related reading: BPC-157 vs TB-500 and the best peptides for inflammation.
This is general information, not medical advice.
