Medicines watchdog to investigate UK peptide clinics over health claims

The medicines regulator is investigating whether UK clinics are breaking the law by making claims about the benefits of unregulated, experimental peptide therapies, the Guardian can reveal.

Interest in experimental peptides has boomed in recent years. The substances are delivered by injection and are touted by sellers, influencers and even some medics as aiding everything from anti-ageing to recovery from injury.

There is little scientific evidence to support such health and wellness claims in humans. Where studies have been carried out, most are in animals or cells.

The Medicines and Healthcare products Regulatory Agency (MHRA) has said clinics are not permitted to make medicinal claims for the peptide treatments offered by their service.

An MHRA spokesperson said: “If clinics offering peptide injections make medicinal claims for those treatments, the products will be considered medicines and subject to regulation under the Human Medicines Regulations 2012.

“The MHRA will take action against clinics which are identified as breaching the legal requirements.”

However, a Guardian investigation has found a number of clinics operating in the UK offering a variety of unregulated, experimental peptides and making a host of claims about their benefits on their websites.

These include approved prescription weight-loss medications based on synthetic peptides that mimic natural hormones, such as semaglutide and tirzepatide, found in weight loss drugs such as Wegovy and Mounjaro respectively. But many other peptides on the market have not undergone the strict regulatory processing that those used in medications have undergone, and remain experimental.

Read full story

Source: The Guardian, 4 April 2026