GLP-1 peptides in the UK: semaglutide, tirzepatide and retatrutide
Prescription-only where licensed, unlicensed where not, and the most counterfeited medicines in the country.
01The short version
Semaglutide, tirzepatide and the not-yet-licensed retatrutide are the peptides most people in the UK are now searching for. They are weight-loss and diabetes medicines, prescription-only where licensed, and the single most counterfeited category of medicine in the country. This is a legal and safety guide, not a buying guide: COGENT does not sell them and would not.
02What they are
GLP-1 receptor agonists mimic a gut hormone that signals fullness and regulates insulin. Semaglutide (Ozempic, Wegovy) is a GLP-1 agonist; tirzepatide (Mounjaro) adds GIP; retatrutide adds glucagon receptor activity and is in phase 3 trials with striking weight-loss results but no licence yet. All are injected weekly.
03Legal position in the UK
Semaglutide and tirzepatide are licensed prescription-only medicines. Legal routes: an NHS prescription (restricted criteria) or a registered private prescriber and pharmacy, including regulated online clinics. Anything else is unlawful supply. Retatrutide has no licence, so every UK sale is of an unlicensed, untested product, and "research grade" retatrutide vials are exactly that.
Buying for personal use is not an offence for the buyer. That is the only reassuring sentence in this section.
04The counterfeit problem
The MHRA has repeatedly warned about fake Ozempic and Wegovy pens sold through social media and unregistered websites, some containing insulin (dangerous) and some containing nothing. Research-vial GLP-1s are un-assayed by definition. The side-effect profile of the real thing (nausea, vomiting, pancreatitis risk, gallbladder problems, muscle loss) needs prescriber monitoring; a counterfeit adds unknown risks on top.
05Where this site stands
These are effective medicines that need a doctor. If weight is the goal, a regulated prescriber is the route, and the NHS and private clinics both offer it. COGENT's interest in peptides is cognitive, and the two we make are covered in the Semax guide and the Selank guide.
COGENT makes two peptide nasal sprays, Semax (FOCUS-01) and Selank (CALM-02), and nothing else. We do not sell the compounds discussed below and this article does not recommend buying them. It exists because people search for these things and deserve an honest answer.
This article is general information, not medical advice. FOCUS-01 and CALM-02 are not licensed medicines and are not intended to diagnose, treat, cure or prevent any condition. If you take prescribed medication, are pregnant or breastfeeding, or are under 18, speak to a doctor before using any peptide product.
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