3 of 6
Orders that turned out to be scams
In the 2024 study, three of six sellers never shipped. They asked for another $650 to $1,200 in fake customs fees instead.
Source: Ashraf et al., 2024a
Fake and laced research peptides
Know what's in the vial.
Research peptides sold online keep failing lab tests, and some sellers never ship. Learn to check a vendor and its paperwork before you trust either, with a source behind every claim.
The label
Retatrutide, 10 mg. The seller printed that, and nobody checked it before sale.
The vial
Unverified. Lilly warns illicit reta may contain contaminants, impurities, or the wrong ingredients entirely (Lilly, 2026). Only a lab test of this vial tells you what's inside.
Tested after purchase
7.7%: The lowest purity a 2024 study measured in semaglutide vials that promised 99% (Ashraf et al., 2024b).
The same vials held 28.56% to 38.69% more semaglutide than their labels said, and all three carried bacterial endotoxin.
| Measure | Purity |
|---|---|
| Advertised purity | 99% |
| Best vial tested | 14.37% |
| Worst vial tested | 7.7% |
Other tests found the same kind of problem.
41.6–71.1%
Research peptide samples that failed quality checks
An April 2026 preprint pooled 6,441 test results across 14 peptides, reta included. The range depends on which quality standard the authors applied.
Source: Mendias & Awan, 2026 (not peer-reviewed)
15%
Samples with measurable endotoxin
Of the 243 samples in that preprint with endotoxin data, 15% had a measurable amount of the bacterial toxin.
Source: Mendias & Awan, 2026 (not peer-reviewed)
Retatrutide status, September 2026
No regulator has approved retatrutide.
Still in trials
Lilly plans to file with the FDA in early 2027 (Lilly, 2026).
Legal only in trials
The only legal way to get it is inside Lilly's clinical trials (Lilly, 2026).
Sold anyway
Lilly has reported more than 14,000 websites, ads, and social media posts selling it, and filed six lawsuits (Lilly, 2026).
Any reta you buy online came from someone other than Lilly.
Three checks before you trust a vendor.
Each one catches a different kind of fake. None of them replaces a lab test of your own vial.
Step 1
Is the company real?
Find it in a state business registry, see how old its website is, and watch how it wants to be paid.
Check the companyStep 2
Is the COA real?
Match the lot number, make sure the lab has no ties to the vendor, and confirm the report with the lab yourself.
Check the COAStep 3
Test your own vial.
A vendor's COA covers someone else's sample. Ask a lab to test identity and purity, the amount in the vial, and endotoxin.
Plan a testPaperwork
A COA is a claim until you check it.
- 1The lot matches your vial. ICH Q7 says a certificate should name the batch it covers (ICH Q7).
- 2Identity comes from mass spec. A retention time on its own isn't specific enough (ICH Q6A).
- 3Endotoxin has its own result. USP chapter 85 covers the test (USP <85>).
- 4The lab confirms it. Look the report up through the lab's own site. Accreditation bodies warn that fake certificates circulate (UKAS).
| 1Lot or batch | SAMPLE-LOT-000 |
|---|---|
| 2Identity | LC-MS: matches expected mass |
| Purity | HPLC-UV: 98.6% |
| 3Endotoxin | LAL test: below limit |
| 4Report number | EX-0000-SAMPLE |
Regulators are going after illegal peptide sellers.
Warning letters to research-use-only sellers
FDA said the sellers' own marketing showed their vials were drugs meant for people, whatever the label said (FDA, 2026) (FDA, 2026).
A label doesn't make a sale legal
Health Canada named BPC-157, TB-500, and retatrutide, and said a research-use-only label "does not make these products legal" (Health Canada, 2026).
Peptide suppliers put on notice
The TGA warned that unapproved peptides may contain the wrong ingredients or fail sterility standards (TGA, 2026).
More than 2,000 pens seized
The UK regulator seized unlicensed retatrutide and tirzepatide pens at an illegal factory (MHRA, 2025).
Had a bad reaction?
Emergency and poison numbers for the US, UK, Canada, and Australia are on the bad batch page.
Sources for this page
- Identify Real Lilly Medicine
Lilly warns that illicit retatrutide, often sold under a "research use only" pretext, may contain harmful contaminants, impurities, or the wrong ingredients entirely.
- Multifactor Quality and Safety Analysis of Semaglutide Products Sold by Online Sellers Without a Prescription: Market Surveillance, Content Analysis, and Product Purchase Evaluation Study
Of 317 online pharmacy links, 134 led to 59 illegal sites; test vials were 7.7% to 14.37% pure, held 28.56% to 38.69% more semaglutide than labeled, and all had endotoxin.
- Lilly's triple agonist, retatrutide, successful in two additional Phase 3 obesity trials, delivering significant improvements in weight and A1C
Lilly reports two more successful Phase 3 retatrutide obesity trials and says it plans to submit a Biologics License Application to FDA in Q1 2027.
- What to know about retatrutide: An investigational triple hormone receptor agonist
Lilly states that no regulatory agency has approved retatrutide and that it is legally available only through Lilly's clinical trials.
- Lilly calls on online platforms, payment companies and regulators to shut down the illegal retatrutide black market
Lilly says no retatrutide medicine is approved anywhere; it filed six new lawsuits, referred 200+ parties to authorities, and reported 14,000+ sites, ads, posts and listings in 100+ countries.
- Q7 Good Manufacturing Practice Guidance for Active Pharmaceutical Ingredients Guidance for Industry
ICH Q7 says a COA should list product name, batch, release and expiry or retest dates, each test's limits and numerical results, a dated quality signature, and the original maker's contact details.
- Specifications: Test Procedures and Acceptance Criteria for New Drug Substances and New Drug Products: Chemical Substances Q6A
ICH Q6A says identification solely by a single chromatographic retention time is not specific, and the guideline does not adequately cover higher molecular weight peptides.
- <85> Bacterial Endotoxins
USP says the Pharmacopeial Discussion Group approved the <85> Bacterial Endotoxins Test as a harmonized standard, official in USP since December 1, 2012.
- Counterfeit certificates and false claims of UKAS accreditation
UKAS warns of counterfeit certificates and organizations falsely claiming UKAS accreditation for management systems certification, and names the ones it knows about.
- Peptide Partners LLC - 735063 - 08/24/2026
FDA says the company's "research use only" products, including one sold as "GLP-3 Reta," are drugs for human use, and that selling bacteriostatic water provides the means to prepare an injectable drug.
- Royal Peptides LLC - 734884 - 08/24/2026
FDA says the company marketed bacteriostatic water alongside a "peptide guide" and "peptide calculator," which together provide the means to prepare an injectable drug.
- Think twice before injecting peptides bought online: unauthorized products can seriously harm you
Health Canada lists BPC-157, TB-500 and retatrutide among seized unauthorized injectable peptides and says "research use only" labels do not make them legal.
- Unapproved peptide product promoters and suppliers are put on notice
TGA warns that unapproved peptides may contain the wrong ingredients, be contaminated or fail sterility standards, and says labeling a blank vial counts as manufacture.
- MHRA smashes major illicit weight loss medicine production facility in record seizure
MHRA seized more than 2,000 unlicensed retatrutide and tirzepatide pens at an illicit Northampton production facility and notes retatrutide has not been approved for UK use.
- Safety and Risk Assessment of No-Prescription Online Semaglutide Purchases
Only 3 of 6 semaglutide orders arrived, scam sellers sought $650 to $1,200 more, and vials tested 7% to 14% pure vs 99% claimed with 29% to 39% extra drug; one had elevated endotoxin (8.95 EU/mg).
- Evaluation of Research Grade Peptides Marketed Directly to Consumers Reveals Extensive Variability in Purity and Measured Abundance Not peer-reviewed
A preprint of 6,441 Finnrick-tested samples across 14 peptides finds 41.6% to 71.1% failed basic quality criteria, and 15% of 243 endotoxin-tested samples had measurable endotoxin.