The wolverine stack is two peptides sold together, and no controlled study has given the pair to people. The side-effect record for BPC-157 and TB-500 sits inside an FDA review prepared for a July 2026 advisory committee, and it is shorter than the sales pages suggest.
Direct answer: no trial has measured wolverine stack side effects, because no trial has given BPC-157 and TB-500 together to humans. The human material is five small BPC-157 studies given by enema, joint injection, bladder instillation and intravenous infusion, three case reports in FDA’s adverse-event database, and one concern the agency’s reviewers state twice, which is immune reactions to an injected peptide.
That gap matters more than any symptom list. A reader asking whether the vial in a clinic fridge will cause a problem is asking for a rate, and no rate exists.
What The Stack Contains
BPC-157 is a 15-amino-acid peptide, and its compound record carries the FDA status and the human study list. TB-500 is a seven-amino-acid peptide that FDA’s reviewers describe as proposed for intramuscular and subcutaneous injection, with a separate record on the site. Neither one is a component of an FDA-approved drug, neither has a USP drug substance monograph, and both reviews arrive at the same place: no human safety data for the way these products reach buyers.
The stack pairs them in one vial on the theory that a repair signal in the gut and a cell-migration signal in connective tissue work better together. That theory comes from rodent work. FDA’s reviewers weighed the two substances for the 503A compounding list and proposed leaving both off it, citing substances that are not well characterized, no human safety data, and a risk of immune reactions through the injection route.
Wolverine Stack Side Effects: What The BPC-157 Studies Recorded
Five clinical studies have given BPC-157 to people. FDA’s reviewers list the routes: rectal enema up to 2 mg per kilogram once daily for eight days in 24 healthy subjects, an 80 mg enema once daily for two weeks in roughly 26 people with ulcerative colitis, 2 to 4 mg into the knee joint in 17 people with knee pain, 10 mg into the bladder in 12 people with interstitial cystitis, and 10 mg then 20 mg by intravenous infusion in two healthy subjects.
The safety result across those five studies is a sentence with three qualifiers inside it. In FDA’s words, “No serious adverse events appear to have been reported with these studies.” The reviewers then add that the studies were short, small, used exploratory doses, and provided limited safety information, and that safety monitoring for most of them is unclear.
One symptom pair does appear. In two meeting abstracts from 2002 and 2003, quoted inside the FDA review, headache and flatulence were the most frequent adverse events after BPC-157 enemas in healthy subjects.
The routes matter more than the doses here. Enema, joint injection, bladder instillation, intravenous drip. FDA’s conclusion states it plainly: “We found no studies that administered BPC-157 to humans via the proposed oral, SC, nasal, or transdermal ROA.” The route used by anyone injecting the stack under the skin has no human safety record behind it.
Absorption data points the same way. In the two enema studies that measured plasma, BPC-157 was not detected in blood. The reviewers found no human pharmacokinetic data for the oral, subcutaneous, nasal or transdermal routes at all.
Wolverine Stack Side Effects: What TB-500 Adds
Nothing, in safety terms, because TB-500 has no recorded human dosing in a study that FDA could find. The TB-500 review, dated May 15, 2026, states that the nomination did not include and FDA did not identify “any clinical studies or human exposure data using TB-500 via any ROA.” Its conclusion is a single line worth keeping: “potential safety risks associated with the use of TB-500 in humans are unknown.”
The searches behind that line ran through March 26, 2025. The adverse-event database returned no reports for TB-500, and the published literature held no case reports. The food and supplement complaint system returned two cases describing a blended TB-500 and BPC-157 product, and the reviewers note those reports carried no safety assessment.
The reviewers state that they did not identify carcinogenicity studies for either peptide, and that they did not identify repeat-dose toxicity studies for TB-500. They add that the clinical relevance of the animal work is unknown, and that no nonclinical toxicity studies of TB-500 inform safety for use in people.
Three Case Reports In The Adverse-Event Database
The BPC-157 review searched FDA’s adverse-event database through December 4, 2025 and retrieved three reports, all for injectable product. They are the closest thing to human safety data on the stack, and they are individual stories.
A 55-year-old woman reported nine days of redness and swelling around an injection site after BPC-157 compounded by Promise Pharmacy. She was also injecting compounded thymosin, which limits what the report can support.
A 28-year-old man reported shortness of breath after subcutaneous BPC-157 acetate compounded by Revive Rx Pharmacy, given for injury and inflammation, and the episode led to an emergency room visit. The report carries no duration of use, no concomitant medications and no timing relative to the injection.
A 40-year-old woman injected a product containing BPC-157 and TB-500 twice daily for joint and wound healing support. The product was labeled for research purposes only and came from Cellular Peptide LLC. She developed diffuse hyperpigmentation and gingival darkening after one week, the reaction returned when she was rechallenged two weeks later, and it stopped when she stopped the peptides. The reviewers call the reaction likely due to the drug product because it repeated on rechallenge, and then add that a product holding two peptides does not allow them to assess a relationship to BPC-157 alone.
FDA’s summary line for all three is the honest one: “it is unclear whether these AEs were attributable to BPC-157.”
A detail worth noting is why the combination case appears in the BPC-157 review rather than the TB-500 one. The two searches closed on different dates, December 2025 for BPC-157 and March 2025 for TB-500. A report filed in between lands in one document and not the other, so a count of zero from one database covers only the reports filed before its closing date.
The Immune Reaction Concern
FDA’s reviewers raise immunogenicity in both documents, in nearly identical language. Peptides can clump into aggregates, aggregates can trigger an immune response, and the subcutaneous route carries more of that risk than swallowing a tablet or taking an enema.
Their wording for BPC-157: as a 15-amino-acid peptide given by a parenteral or nasal route, it “may pose a significant risk for immunogenicity, potentially amplified by aggregation as well as potential peptide-related impurities.”
Their wording for the consequence is broad. An immune response can run from “antibody responses with no apparent clinical manifestations to life-threatening and catastrophic reactions,” and one outcome is neutralizing antibodies that remove the effect of the peptide and of the body’s own version of it.
No study has measured the immunogenicity of a BPC-157 product, and the reviewers state that they did not find one. Product formulation, peptide concentration and storage conditions all feed the same risk, because each one can generate the impurities and aggregates that provoke the response.
What A Reader Can Check
Ask the prescriber four questions before paying for a stack.
- Which peptide and which form: free base and acetate are different substances with different supporting documents.
- Which pharmacy compounds it, and whether that pharmacy operates under section 503A or 503B.
- What monitoring comes with it, including what to do if a reaction starts.
- Whether any human study covers that injection route for both peptides together.
Doses vary by prescriber, pharmacy and product, and we publish no protocol for either peptide. That decision belongs to a clinician who has your history and your medication list. Our earlier piece on wolverine stack dosage explains why the only published numbers come from rats.
Our clinic directory lists practices by city with the state board lookup for each one, and we flag each listing as unverified until the business confirms its own details, so check the license before you book. For the wider regulatory picture on these two peptides, our report on the FDA advisory committee and compounding covers what the committee did and did not do.
Frequently asked questions
What are the side effects of the wolverine stack?
No study has measured them for the combination. The individual peptides have injection-site reactions, headache and flatulence in the small BPC-157 enema studies, three case reports in FDA’s adverse-event database, and a stated risk of immune reactions from the injection route. No rate exists for any of it.
Has the wolverine stack ever been tested in people?
No. FDA’s reviewers found no human exposure data for TB-500 by any route, and the BPC-157 human studies used enemas, joint injections, bladder instillation and intravenous infusion rather than the subcutaneous injection sold as the stack.
Is BPC-157 FDA approved?
No. It is not a component of any FDA-approved drug and has no USP monograph. In briefing documents prepared for the July 23 and 24, 2026 advisory committee meeting, FDA’s reviewers proposed not adding BPC-157 or TB-500 to the 503A compounding list.
What did FDA’s reviewers say about immune reactions?
Both documents warn that injected peptides may provoke an immune response, that aggregation and peptide impurities raise the risk, and that no study has measured immunogenicity for either product. The stated range of outcomes runs from a silent antibody response to a life-threatening reaction.
How long were people followed in the BPC-157 studies?
Two weeks at most. The enema studies ran eight days and two weeks, and the reviewers note that short duration and small size leave long-term safety unmeasured.
Are there cancer studies for either peptide?
No. FDA did not identify carcinogenicity studies for BPC-157 or TB-500, and the reviewers state that the clinical relevance of the rodent work is unknown.
What should you ask a clinic selling the wolverine stack?
Ask which peptide and form, which pharmacy and under which section of the law, what monitoring is included, and whether any human study covers the route in question for both peptides. A clinic that cannot name the pharmacy and the prescriber has nothing behind the protocol.
Sources:
U.S. Food and Drug Administration, FDA Briefing Document, Pharmacy Compounding Advisory Committee Meeting July 23-24, 2026: FDA Evaluation of BPC-157-Related Bulk Drug Substances, dated May 11, 2026. fda.gov
U.S. Food and Drug Administration, FDA Briefing Document, Pharmacy Compounding Advisory Committee Meeting July 23-24, 2026: FDA Evaluation of TB-500-Related Bulk Drug Substances, dated May 15, 2026. fda.gov
U.S. Food and Drug Administration, July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee, meeting page and agenda. fda.gov
U.S. National Library of Medicine, ClinicalTrials.gov, NCT02637284, oral BPC-157 phase 1 study in healthy subjects, no results posted, as described in the BPC-157 briefing document, record checked November 5, 2026. clinicaltrials.gov
Meeting abstracts from 2002 and 2003 on BPC-157 enema administration, quoted second-hand in the FDA BPC-157 briefing document dated May 11, 2026, which is the source for the headache and flatulence finding. fda.gov
We report published research and regulatory documents. This is not medical advice, and it is not a recommendation for or against any product. Compounded substances are not FDA-approved, and risks and suitability vary by person. Talk to a licensed prescriber about your own situation before you start, stop or pay for anything.