The short answer: nobody knows BPC-157's full side-effect profile in people, because it has never been measured in a proper trial. FDA found five small human studies covering about 80 people. No serious adverse events were reported, but the studies were short and safety monitoring was mostly unclear.
Where nothing has been measured, this post says so.
Status as of November 6, 2026: BPC-157 is not FDA-approved for any use. Under an HHS policy filed October 28, licensed pharmacies and doctors can compound it without enforcement action, within set limits. That isn't approval, and it isn't safety data. PubMed and ClinicalTrials.gov were searched November 6. This isn't medical advice or a dosing guide. If you take medicines or have a health condition, ask your doctor.
Key takeaways
FDA's July 2026 review found "insufficient clinical safety information" and no human study of BPC-157 taken by mouth, under the skin, by nose or through the skin.
Liver: ALT ran 24% higher in female rats at the lowest dose tested, 14 days after treatment ended. FDA wasn't convinced it was incidental.
Blood thinners: no human interaction data exists. In 28-day animal tests, a clotting measure fell about 10% in male rats and rose 20% to 25% in male dogs.
Cancer: FDA found no carcinogenicity studies, so the risk is untested in either direction.
The vial is a separate risk. In a 6,441-sample preprint across 14 peptides, 41.6% to 71.1% failed basic quality criteria.
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What are the side effects of BPC-157?
The reported list is short, and short here means unmeasured, not clean. In the enema studies in healthy people, the most frequent complaints were headache and flatulence (FDA briefing document, July 2026). Here's all the human exposure FDA found.
How it was given | People | How long | Safety detail reported |
|---|---|---|---|
Rectal enema, healthy people | 24 | Up to 8 days | Headache, flatulence |
Rectal enema, ulcerative colitis | About 26 | 2 weeks | No serious events reported |
Knee injection | 17 | 1 or 2 injections | No serious events reported |
Bladder injection | 12 | One procedure | No adverse events reported |
IV infusion | 2 | 2 days | No side effects reported |
By mouth, under the skin, nasal, on the skin | 0 published | None | Nothing to report |
Sources: FDA briefing, Lee et al., 2024, Lee & Burgess, 2025. A 2026 review counted three studies and 30 people, without the enema work (Poolton et al.).
FDA's adverse event database added three reports through December 2025, all injected: injection-site redness and swelling, shortness of breath that led to an ER visit, and darkened skin and gums. FDA couldn't tie any of them to BPC-157 alone. The details are in BPC-157 for knees and shoulders.
Is BPC-157 safe?
Nobody can say it is. FDA concluded "there is insufficient clinical safety information to characterize the safety profile." USADA says "it is unknown if there is a safe dose" (USADA), and it's banned in tested sport under WADA's S0 category.
BPC-157 side effects by organ
In people | Healthy animals, 28 days | Rodent injury models | |
|---|---|---|---|
Liver | Two-person pilot: no measurable change | Signals in female rats. FDA unsure | Reported protection |
Heart | Same pilot: no measurable change | Dog ECGs unremarkable | Reported protection |
Kidney | Same pilot: no measurable change | Lower creatinine in dogs, reversed | Reported protection |
Anxiety, mood | Never measured | Rats' general behavior unchanged | Mixed results |
Clotting | Never measured | Moved in opposite directions | Less bleeding reported |
A warning on the right-hand column: "protects an injured rat" doesn't mean "safe for a healthy person." And 175 of the 230 BPC-157 papers in PubMed on November 6 list the same Zagreb researcher as an author.
Is BPC-157 bad for your liver?
Unknown in people, and the one animal toxicity paper left FDA with a question.
Fourteen days after treatment ended, female rats given the lowest dose tested had ALT 24% higher, glucose 31% higher and triglycerides 87% higher than controls. Their livers weighed about 20% more relative to body size. High ALT "may be a sign of a liver injury or disease" (MedlinePlus).
The authors called these incidental, since values stayed in the normal rat range. FDA wrote that it's "unclear" they "can be definitively interpreted as incidental findings." FDA also says organs in dogs were unaffected "except the liver," gives no detail, and notes the paper left out its tissue data (FDA briefing; Xu et al., 2020).
Pointing the other way, rodent studies report less liver damage after bile duct blockage and radiation (Sever et al., 2019; Huang et al., 2022).
Does BPC-157 affect the heart?
No heart harm has been shown, and almost nothing has been measured. In that pilot, two people showed "no measurable effects" on tested heart, liver and kidney markers (Lee & Burgess, 2025). Dog ECGs showed "no remarkable differences" from controls after 28 days (FDA briefing).
Rat studies report protection against arrhythmias and induced heart attacks (Balenovic et al., 2009; Barisic et al., 2022). I found no published blood pressure or heart rhythm data from a group of people taking it.
Is BPC-157 hard on the kidneys?
Unknown. The two-person pilot is the only human kidney data, nothing has been published in people with kidney disease, and FDA says there's "no information to assess the pharmacokinetics of BPC-157 in humans."
In 28-day dog tests, creatinine fell 18% in females and 26% in males at the top dose, then returned to normal. High creatinine is the usual kidney warning, so this isn't the classic damage pattern, though low levels have their own causes (MedlinePlus). The authors' explanation, tied to muscle healing, didn't satisfy FDA, which noted no reported muscle injuries in the dogs. Rat studies report protection from an antibiotic's kidney damage (Vukoja et al., 2026).
Does BPC-157 cause anxiety?
Nobody has measured it. I found no human study that tracked anxiety or mood, and none of FDA's three adverse event reports describes either.
A 2001 paper reported less fear in one rat test and control-like behavior in part of a mouse test (Sikiric et al.). A 2004 McGill study, with Sikiric as a co-author, found serotonin synthesis rose in some rat brain regions and fell in others, mechanism unknown (Tohyama et al.). Direction and size in people are unknown.
Does BPC-157 interact with blood thinners?
There's no human data. A PubMed search on November 6 found no study of BPC-157 with apixaban (Eliquis), rivaroxaban, dabigatran, edoxaban or ticagrelor, and FDA's review cites no interaction study.
Rat studies. With heparin, warfarin or aspirin on board, BPC-157 reduced bleeding after tail amputation, though it didn't change heparin's activity on one test (Stupnisek et al., 2012). It also counteracted the anti-platelet effects of aspirin, clopidogrel and cilostazol (Konosic et al., 2019). Sikiric is an author on both.
Healthy animals. aPTT, a clotting time, was about 10% shorter in male rats and 20% to 25% longer in male dogs, statistically significant at one dog dose. FDA called this "suggestive of altered clotting properties." Shorter aPTT is a known risk factor for clots, longer for bleeding (FDA briefing).
So the question isn't only "will I bleed more?" The rat data also raises whether a drug you depend on could work less well. Your prescriber needs to know about anything you're taking, and blood thinners aren't something to change on your own.
Does BPC-157 cause cancer?
Nobody has shown that it does, and nobody has run the test that would show it doesn't. FDA found no carcinogenicity studies, which are normally done when use could total 6 months or more (FDA briefing).
What is established: BPC-157 promotes new blood vessel growth, or angiogenesis, in lab and animal models, including from teams outside Zagreb (Hsieh et al., 2017; Zhang et al., 2026). Tumors need blood supply, so people worry. That's a mechanism argument, not a finding, and researchers disagree:
The concern. A Polish team wrote that "pro-angiogenic signaling remains a plausible tumor-promoting hazard" (Józwiak et al., 2025).
The rebuttal. Sikiric's group claims "prominent anti-tumor potential," leaning on a melanoma cell line, an unpublished mouse result and a cancer-wasting mouse study (Sikiric et al., 2025).
The reply. The Polish team called the cell-line work "insufficient to support anticancer claims." In the wasting study, tumor volume wasn't significantly different (Józwiak review).
BPC-157 did pass three standard DNA damage tests. That's a narrower question than whether it could feed a tumor that already exists. If you've had cancer, this belongs with your oncologist.
Can BPC-157 trigger an immune reaction?
Possibly, and it hasn't been tested. FDA "did not identify any studies that formally investigated the immunogenicity of BPC-157 products." So this is a warning, not a record of harm.
By route. Injected or nasal BPC-157 "may pose a significant risk for immunogenicity." By mouth, the inherent risk "is likely to be low."
What raises it. Aggregates, which are peptide chains clumping together, and peptide-related impurities.
What it could look like. Anything from antibodies with no symptoms to "life-threatening and catastrophic reactions," often unpredictably.
Is contamination a different risk from BPC-157 itself?
Yes. Everything above is about the molecule. This is about what's actually in the vial.
FDA's review found:
"Multiple salts, and derivatives" sold under the same common name, so a label may not tell you which substance you have.
No USP drug monograph, meaning no official standard to test against.
"Most CoAs" it found "only contain purity testing results," with no impurity limits.
No endotoxin or bioburden results in the nomination files.
The broadest data covers peptides generally, not BPC-157 alone. A preprint of 6,441 samples across 14 peptides found 41.6% to 71.1% failed basic quality criteria, and 15% of samples tested for endotoxin had a measurable amount (Mendias & Awan, 2026). It hasn't been peer reviewed. The breakdown is here.
Of FDA's three adverse event reports, two involved compounded products and one a "research purposes only" product. HHS says FDA doesn't review compounded drugs for "safety, effectiveness, or quality" before they're marketed (HHS notice, Oct 30, 2026). See what the HHS pass covers. Compounders generally don't report adverse events to FDA either, so three is a floor.
Purity says nothing about endotoxin or sterility. See how to test peptides for purity and how to read a COA.
What still hasn't been measured?
Long-term use. Human exposure in FDA's list tops out at two weeks. Animal toxicity dosing stopped at 28 days.
The routes people actually use. No human study by mouth or under the skin.
Pregnancy. One rat study found no birth defects. Nobody has studied a full reproductive cycle.
The only real trial on the registry that could add placebo-controlled data is a rotator cuff study of about 30 people, and it hasn't started (NCT07803250). I'll update this post when it reports.
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If you've had a side effect you think came from BPC-157, reply and tell me what happened and whether a doctor looked at it. Please leave vendor names out.
BPC-157 side effects FAQ
Can BPC-157 raise liver enzymes?
It hasn't been shown in people. In one 28-day study, female rats had 24% higher ALT 14 days after stopping, and FDA isn't sure that was incidental.
Can you take BPC-157 with Eliquis or warfarin?
No human study has tested either combination. Rat work with warfarin, heparin and aspirin suggests BPC-157 can change bleeding and platelet results. Ask your prescriber.
Does BPC-157 grow tumors?
That's untested. It promotes blood vessel growth in lab models, which is why researchers worry, but FDA found no carcinogenicity studies. Claims that it fights cancer aren't backed by published tumor-growth studies either.
Is oral BPC-157 safer than injecting it?
No human study has given it by mouth or under the skin. FDA considers the inherent immune risk likely low by mouth and potentially significant by injection, but it still flagged impurities for oral products. What each route has been tested for is in BPC-157 oral vs injection.
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