Where to buy Tirzepatide in the UK: the licensed route is a prescription, and the sellers with a verifiable COA
Tirzepatide is Eli Lilly's Mounjaro, a prescription-only medicine licensed by the MHRA for type 2 diabetes and, since November 2023, weight management, so the licensed route is a prescription from a pharmacy; research-vial sellers offer unlicensed copies. If you are buying it anyway, the only thing you can check is the certificate: the newest verifiable Tirzepatide certificate on any UK seller's website is on Lab77Peptides (lab77peptides.uk), analysed 25 Sep 2026 (task #231386 on Janoshik's site); 3 verified sellers hold one covering Tirzepatide, listed newest first below. It is a licensed prescription medicine, not a research peptide, so it sits in a tighter legal category The Peptide Watch does not list vendors for and does not endorse buying outside a prescription.
Who holds the newest Tirzepatide report (3 verified UK sellers)
| Seller | Newest Tirzepatide report | Age of that report | |
|---|---|---|---|
| Lab77Peptides lab77peptides.uk | 25 Sep 2026 | 25 days | verify |
| Biovanta biovanta.store | 27 Aug 2026 | 1 month, 23 days | verify |
| BioVanta Research biovantaresearch.com | 25 May 2026 | 4 months, 25 days | verify |
Newest report first. Every report was opened on Janoshik's own website and names the seller as the client. The date is the analysis date printed on the report. The verify link opens the laboratory, never the shop. Audit findings, not recommendations.
A record of paperwork, not a recommendation: The Peptide Watch sells nothing, takes no money from sellers and links to none of them.
Why the date matters · What purity means · What Tirzepatide is · Regulators · Every report
Every Tirzepatide purity report we have read (4), one row per report
The 4 verifiable Tirzepatide certificates we have read, newest first
Each row was opened on Janoshik's own site by a real page load and transcribed. The client column is the name the laboratory printed; a certificate counts as a seller's own only when that name is the seller. The report date is the analysis date printed on the report where we have read it, otherwise the date the laboratory received the sample. The verify link opens the laboratory, never the shop. Audit findings, not recommendations.
| Seller | Task | Client on the report | Report date | Result | Batch | |
|---|---|---|---|---|---|---|
| Lab77Peptides | #231386 | Lab77peptides.uk | 25 Sep 2026 | Tirzepatide · 10.96 mg · 99.568% | L77Tirz2612 | verify |
| Biovanta | #216993 | BioVanta | 27 Aug 2026 | Tirzepatide · 17.72 mg/ml · 99.588% | Ti40-20260508 | verify |
| Lab77Peptides | #193655 | Lab77Peptides.co.uk | 11 Jun 2026 | Tirzepatide · 11.18 mg · 99.301% | 77TZ265 | verify |
| BioVanta Research | #153880 | Biovanta Research | 25 May 2026 | Tirzepatide · 5.15 mg · 98.074% | TRZ-653ST | verify |
Why the date on a certificate matters
What a purity figure means
The purity on a Janoshik report is the share of the main peak in an HPLC chromatogram. 99.5% means that 99.5% of what the detector saw was one substance and 0.5% was something else. It is not the amount in the vial: that is the separate quantity line, in milligrams. It does not by itself prove which substance the peak is: that is identity, confirmed by mass spectrometry. And it says nothing about sterility, endotoxins or heavy metals, which are separate tests.
A purity figure printed on a shop page with no report behind it is a claim, not a measurement. Between two reports, the difference that matters is rarely 99.2% against 99.8%; it is whether the report exists at all, names the seller as the client, covers this compound on its own, and is recent.
What Tirzepatide is, and what it is sold as
Tirzepatide is a dual-agonist GLP-1 compound (the active ingredient in Mounjaro). Tirzepatide is Eli Lilly's Mounjaro, a prescription-only medicine licensed by the MHRA for type 2 diabetes and, since November 2023, weight management, so the licensed route is a prescription from a pharmacy; research-vial sellers offer unlicensed copies.
| Development status | Licensed medicine. MHRA marketing authorisation for type 2 diabetes and, since 8 November 2023, for weight management; also licensed in the EU and US. |
|---|---|
| Originator | Eli Lilly and Company, as LY3298176. Rights: Eli Lilly and Company, sold as Mounjaro and Zepbound. |
| Registered clinical trials | 283 on ClinicalTrials.gov |
A licensed prescription medicine, and one of the most studied drugs of the decade. PubMed indexes 2,493 papers on tirzepatide, including 144 clinical-trial reports and 66 phase 3 reports; ClinicalTrials.gov lists 283 registered trials. It is Lilly's Mounjaro.
In the UK it is prescription-only. The MHRA authorised Mounjaro for type 2 diabetes and, on 8 November 2023, for weight management in adults with a BMI of 30 or more, or 27 or more with a weight-related condition. That means a pharmacist dispensing a Lilly pen against a prescription is the lawful route, and anything sold as a vial of tirzepatide powder for research is outside it.
What a certificate can and cannot tell you here. A verifiable Janoshik report on a research-chemical vial says what the powder is and how pure the tested sample was. It says nothing about the licensed product, and it does not make an unlicensed copy lawful to sell as a medicine.
The published record in numbers, and the sources
| Papers on PubMed | 2493 |
|---|---|
| Indexed as rat or mouse studies | 113 |
| Indexed as clinical trials | 144 |
| Published since 2020 | 2491 |
Counts are from PubMed on 15 September 2026 using the queries recorded in our evidence file. A description of the published record, not medical advice and not an argument for or against use.
- Cost-effectiveness of tirzepatide versus semaglutide for patients with obesity or overweight in the US: evidence from the SURMOUNT-5 head-to-head phase-3 trial. (J Med Econ, 2026, PMID 42012820)
- Liver Fat Changes in Patients With Type 2 Diabetes by Presence of Genetic Hepatic Steatosis: A Post Hoc Analysis of SURPASS-3 MRI. (Liver Int, 2026, PMID 42576670)
- Tirzepatide Efficacy and Tolerability According to Early Weight Response: A Post Hoc Analysis of the SURMOUNT-1 and SURMOUNT-2 Trials. (Diabetes Obes Metab, 2026, PMID 42348366)
- Association of tirzepatide with changes in OSA-related measures based on baseline characteristics - post hoc analyses of SURMOUNT-OSA. (J Clin Sleep Med, 2026, PMID 42675225)
- EASL-EASD-EASO Clinical Practice Guidelines on the management of metabolic dysfunction-associated steatotic liver disease (MASLD). (J Hepatol, 2024, PMID 38851997)
- Comparative effectiveness of GLP-1 receptor agonists on glycaemic control, body weight, and lipid profile for type 2 diabetes: systematic review and network meta-analysis. (BMJ, 2024, PMID 38286487)
- Anti-consumption agents: Tirzepatide and semaglutide for treating obesity-related diseases and addictions, and improving life expectancy. (Prog Cardiovasc Dis, 2025, PMID 39743126)
- European Pharmaceutical Review, MHRA authorises Mounjaro for weight management
- House of Commons Library, weight loss medicines in England
What regulators say about Tirzepatide
In the UK. Prescription-only medicine in Great Britain (MHRA marketing authorisation; weight-management use authorised 8 November 2023).
We hold no statement from the FDA, MHRA or EMA specifically about Tirzepatide on file. Its development and licence sources are listed under the record above.
What the 4 Tirzepatide certificates show
We have read 4 Janoshik reports covering Tirzepatide, published by 3 UK sellers. Each was opened on Janoshik's own website. All 4 name the seller itself as the client. All 4 are dated within the last six months. The newest is dated 25 Sep 2026 and the oldest 25 May 2026.
All 4 reports give a purity figure for Tirzepatide. The figures run from 98.074% to 99.588%, and 3 of the 4 are at 99% or above. A purity figure describes the sample the laboratory received, not every vial from that batch.
Read directly from the newest reports: Lab77Peptides: task #231386, analysed 25 Sep 2026, 10.96 mg recovered at 99.568%, client Lab77peptides.uk; Biovanta: task #216993, analysed 27 Aug 2026, 17.72 mg/ml at 99.588%, client BioVanta; BioVanta Research: task #153880, analysed 25 May 2026, 5.15 mg recovered at 98.074%, client Biovanta Research.
A certificate is a batch document. The lines that matter are the compound (it must say Tirzepatide, not only a batch code), the client (the shop, not its supplier) and the analysis date. A new batch is untested until a new report appears.
Questions people ask
Which UK sellers publish a verifiable Janoshik certificate naming Tirzepatide?
As of 20 October 2026, 3: Lab77Peptides, Biovanta, BioVanta Research. Each has a report on Janoshik's own website that names the seller as the client and lists Tirzepatide. That is a statement about paperwork, not a recommendation; The Peptide Watch does not recommend anywhere to buy Tirzepatide.
How recent is the newest Tirzepatide certificate from a UK seller?
The newest we have read is Janoshik task #231386, analysed 25 Sep 2026. It is published by Lab77Peptides and names it as the client. A certificate covers one batch, so an old one says little about stock on sale today.
How do I check that a certificate for Tirzepatide is genuine?
Four things: an independent laboratory is named; the client field names the seller you are buying from, not a supplier; the compound line says Tirzepatide; and the report's task number and key open the same report on the laboratory's own website (verify.janoshik.com). A branded PDF with no laboratory name and no verification code fails on the first check, however professional it looks. The free COA Checker on this site runs the checks for you.
Is Tirzepatide licensed in the UK?
Tirzepatide is Eli Lilly's Mounjaro, a prescription-only medicine licensed by the MHRA for type 2 diabetes and, since November 2023, weight management, so the licensed route is a prescription from a pharmacy; research-vial sellers offer unlicensed copies. The Peptide Watch does not rank or recommend anywhere to buy it, and does not give legal or medical advice.
Why does The Peptide Watch not say where to buy Tirzepatide?
Because the site records paperwork, not recommendations. A verifiable certificate proves that a sample of one batch was tested. It does not prove the vial you receive matches it, and it says nothing about whether you should buy a prescription medicine outside a pharmacy at all. Listing which sellers publish a certificate you can check, and which publish nothing, is as far as the evidence goes.
Tirzepatide in the UK at a glance
| Active UK sellers listing Tirzepatide | 62 |
|---|---|
| Of which publish a verifiable own-name certificate | 3 |
| Of which name no laboratory at all | 21 |
Counted from the vendor ledger at build time. The A-Z directory lists every seller and what each publishes instead.
The Peptide Watch's position on Tirzepatide
Tirzepatide is a regulated medicine. The Peptide Watch audits research-peptide sellers and does not rank or recommend anywhere to buy Tirzepatide; this page exists so the verification standard is clear. If you can verify a seller's testing, you can at least judge its evidence; if you cannot, you are trusting marketing on a regulated medicine sold outside its licensed supply chain. See how UK research-peptide testing stacks up in the market statistics.
Research-use-only information, not medical, dosing or purchasing advice. The Peptide Watch sells nothing and links to no seller. A certificate proves a sample was tested once, not that a specific vial matches it.