Are peptides legal in the UK? The four categories explained

01The short version

Most peptides are legal to possess in the UK. Whether they are legal to sell, and to sell for human use, depends on which category the compound falls into. There are four, and the rules are very different: licensed medicines (prescription only), unlicensed research peptides (legal to buy, sold "not for human use"), nootropic peptides sold as supplements, and controlled substances (a short list, mostly hormones abused in sport). This guide walks through each, as at September 2026, with the caveat that the law is moving and we are not lawyers.

02Prescription-only peptide medicines: semaglutide, tirzepatide, and the rest

Semaglutide (Ozempic, Wegovy), tirzepatide (Mounjaro), liraglutide and insulin are licensed medicines classed as prescription-only (POM). Possessing them with a prescription is legal. Supplying them without one is a criminal offence under the Human Medicines Regulations 2012, and the MHRA prosecutes. Buying them from an unregistered online seller is not itself an offence for the buyer, but the product is frequently counterfeit, and the MHRA has issued repeated warnings about hospitalisations from fake pens.

Retatrutide is different again: it is an investigational GLP-1/GIP/glucagon peptide with no licence anywhere yet. Anything sold as retatrutide in the UK is unlicensed and untested. It is legal to possess; supplying it for human use is not.

03Research peptides: BPC-157, TB-500, ipamorelin, GHK-Cu and the rest

These are not controlled substances and not licensed medicines. They are legal to buy and possess. Sellers get around medicines law by labelling them "for research purposes only, not for human consumption", which shifts the responsibility to the buyer. The MHRA's position is that a product presented for a medicinal purpose is a medicine regardless of the label, so a seller who markets BPC-157 "for injury recovery" is breaking the law even with the disclaimer. A seller who just lists the vial is in a grey area the regulator has not yet closed.

For the buyer the legal risk is low; the practical risk (identity, purity, sterility) is the real one. Research peptides in the UK explains how to read a certificate of analysis.

04Nootropic peptides: Semax and Selank

Neither is a controlled substance, neither is a licensed medicine, and both are sold in the UK as food supplements for healthy adults, which is legal provided no medicinal claims are made. That is why this site talks about attention and working days and never about treating anything. Full detail in Is Semax legal in the UK?.

05Controlled peptides

A small number of peptides are Class C controlled drugs under the Misuse of Drugs Act because of abuse in sport: human growth hormone (somatropin), and growth hormone secretagogues such as GHRP-6 and hexarelin in some readings. Anabolic steroids (not peptides) are in the same class. Possession for personal use is not an offence for Class C anabolic agents, but supply is. If a vendor is selling growth hormone, that is the one to walk away from.

06Sport is a separate rulebook

WADA bans most research peptides (BPC-157, TB-500, all growth hormone secretagogues) and the GLP-1s are under monitoring. Legal in the UK does not mean legal in a tested sport. Semax and Selank are not on the WADA list.

07Summary table

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.