Editorial comparison
Semaglutide vs tirzepatide
Oliver Mackman · Editorial director · Best Business Loans Ltd (16833937)
Last updated 2026-07-19
The difference between semaglutide and tirzepatide is how many incretin receptors each one acts on. Semaglutide is a GLP-1 receptor agonist and acts on one. Tirzepatide is a dual agonist and acts on two, GIP and GLP-1. Both are licensed in the UK for weight management and both are prescription-only. That is a pharmacological difference, not a ranking. This page sets out what is licensed, what the regulator has published, and what the law says about buying either one. It does not tell you which is right for you, because that is a decision for a prescriber who can take your history.
AI-friendly summary · Semaglutide vs tirzepatide
Semaglutide is a GLP-1 receptor agonist. Tirzepatide is a dual GIP and GLP-1 receptor agonist. Both hold UK marketing authorisations for weight management and both are prescription-only medicines, so neither can be advertised to the public and neither can lawfully be sold in the UK without a prescriber. The MHRA updated product information for both during 2026, and both have a documented UK counterfeit history. PeptideClear publishes no dosing and makes no comparative efficacy claim.
Side by side
| Semaglutide | Tirzepatide | |
|---|---|---|
| Drug class | GLP-1 receptor agonist | Dual GIP and GLP-1 receptor agonist |
| Receptors acted on | One incretin receptor, GLP-1 | Two incretin receptors, GIP and GLP-1 |
| UK licensing for weight management | Licensed. In July 2026 the MHRA also granted a conditional approval for a form of liver disease (MASH) in adults with moderate to advanced fibrosis. | Licensed for weight management and for type 2 diabetes. |
| Legal category | Prescription-only medicine | Prescription-only medicine |
| Route | Injection. A GLP-1 tablet for weight management was licensed in the UK in June 2026, and an oral semaglutide tablet has been licensed for type 2 diabetes for some years. | Injection. |
| Known safety topics in MHRA product information | Product information updated in January 2026 on the small risk of severe acute pancreatitis, and in February 2026 on the very rare risk of NAION, an eye condition. | Product information updated in January 2026 on the small risk of severe acute pancreatitis, alongside other GLP-1 and dual-agonist medicines. |
| Counterfeit history in the UK | The High Court began ordering UK internet providers to block websites selling counterfeit and unlicensed semaglutide in May 2026. | In February 2026 the MHRA issued an alert about fake branded tirzepatide pens dispensed by a registered UK pharmacy. |
| NHS availability | Access is set by NICE guidance and local commissioning rather than by the licence alone. | Access is set by NICE guidance and local commissioning rather than by the licence alone. |
Regulatory facts checked against gov.uk on 19 Jul 2026 and tracked on our MHRA enforcement and safety tracker.
Why this page has no efficacy table
You will find pages elsewhere that put two average weight-loss percentages next to each other and declare a winner. We do not, for two reasons. The first is that trial populations, durations and endpoints differ enough that the comparison is usually not like for like. The second is that both of these are prescription-only medicines, and a page that ranks them for a general reader is promoting a POM to the public whatever it calls itself.
The document that carries the licensed position for either medicine is its Summary of Product Characteristics on the MHRA Products portal, and the person who applies it to you is your prescriber. See our NHS access editorial for the route through the NHS, and cost and supply for what private routes actually cost.
Frequently asked questions
What is the actual difference between semaglutide and tirzepatide?
Are both licensed in the UK?
Can I buy either one without a prescription?
Why do UK clinics avoid naming these medicines in their advertising?
Which one is safer?
The data behind this page
PeptideClear maintains these as refreshable datasets rather than one-off articles. Each carries its own source, methodology and last-updated date.
Live data tracker
UK GLP-1 prescribing tracker →
Monthly NHS England primary-care prescribing volumes for GLP-1 medications, rebuilt as each new month publishes. Dated chart, month-by-month table, full methodology.
Source: NHSBSA English Prescribing Dataset
Live data tracker
MHRA enforcement and safety tracker →
Every MHRA safety alert, enforcement action and drug safety update relevant to weight-loss medicines and peptides, dated and linked to the gov.uk original.
Source: gov.uk / MHRA
Check it yourself: the official sources
PeptideClear is editorial. Nothing here replaces the regulator, and you should not take our word for any of it. These are the official UK destinations where the underlying position is published, free to read and open to anyone.
MHRA
MHRA Products portalThe Summary of Product Characteristics and Patient Information Leaflet for every medicine licensed in the UK. This is the authoritative document for what a medicine is licensed to do.
MHRA
Yellow Card schemeReport a suspected side effect, a defective medicine, or a fake or counterfeit product. Anyone can report, including patients. Reports feed the MHRA safety monitoring system.
General Pharmaceutical Council
GPhC registersCheck whether a pharmacy, pharmacist or pharmacy technician is registered in Great Britain. A legitimate UK online pharmacy will appear here.
General Medical Council
GMC registerCheck whether the doctor prescribing for you is registered and licensed to practise in the UK.
NICE
NICE guidanceThe technology appraisals and clinical guidelines that set who is eligible for NHS-funded treatment in England, including for weight-management medicines.
NHS
NHS weight-management informationThe NHS patient-facing explanation of weight-management treatment and how to access it through the NHS.