Can semaglutide be used for weight loss in the UK?

What the STEP 1 trial found, and why the numbers matter

The STEP 1 trial, published in the New England Journal of Medicine, followed 1,961 adults with obesity or overweight plus at least one weight-related condition over 68 weeks. Participants receiving semaglutide 2.4mg weekly lost an average of around 15% of their body weight, compared with roughly 2.4% on placebo, alongside lifestyle changes. That figure is meaningful because it puts semaglutide well ahead of older prescription treatments and deep into territory previously associated with surgery. The results were robust enough that NICE recommended the medicine for NHS use, and the MHRA granted a UK marketing authorisation for Wegovy as a weight-management treatment.

It is worth being precise about which semaglutide product those results refer to. The 2.4mg weekly maintenance dose (the Wegovy formulation) is what the STEP programme studied for weight loss. Ozempic, which tops out at 1mg or 2mg weekly and is licensed for type 2 diabetes, was not tested at those doses for obesity. Searches that blur the two can lead people toward a medicine whose weight-management evidence base looks quite different.

The most recent development in this space is the 7.2mg dose. The MHRA approved it in early 2026, and trials reported approximately 20.7% average weight reduction over 72 weeks, closing the gap with tirzepatide (Mounjaro). A dedicated single-dose pen was cleared for use in April 2026. You can read more about Wegovy's full profile, including how doses are titrated, on our dedicated page.

Which semaglutide products are actually licensed for weight loss

Three semaglutide products are sold in the UK, and they are not interchangeable for weight-loss purposes. Wegovy, the weekly injection, is licensed for weight management in adults with a BMI of 30 or above, or 27 to 29.9 with at least one weight-related condition such as high blood pressure, high cholesterol or obstructive sleep apnoea. It is the product our prescribers work with at nume.

Ozempic shares the same active molecule but its licence is for type 2 diabetes. Prescribing it for weight loss off-label is a clinical decision that falls outside MHRA-approved use; it is not something a responsibly run pharmacy or clinic does routinely. Rybelsus, the oral version, is also licensed for diabetes, not weight loss. If you have seen Rybelsus mentioned in weight-loss contexts online, that reflects its off-label use rather than any approved indication.

From June 2026, there is now a fourth option: the Wegovy tablet. This oral formulation (1.5mg escalating to a 25mg daily maintenance dose) was approved by the MHRA on 11 June 2026 as the first oral GLP-1 weight-loss medicine licensed in the UK. It is genuinely useful for people who prefer not to inject. Storage is simple, no refrigerator needed; the strips sit at room temperature, easy to keep in a bag for travel. You can explore how the oral route fits into the picture on our page covering what Wegovy is used for.

Who the licence covers, and where NHS access stands

The BMI thresholds in the Wegovy licence are 30 and above, or 27 to 29.9 alongside a qualifying condition. Lower thresholds apply for some ethnic backgrounds under UK guidance, specifically a 2.5 kg/m² reduction for South Asian, Chinese, Middle Eastern, Black African or African-Caribbean backgrounds. These are the private prescription eligibility criteria; your prescriber assesses the full clinical picture, not just the number on the scale.

NHS access is more restricted. NICE's appraisal of semaglutide for weight loss, TA875, recommends it only within specialist weight management services, for a maximum of two years, and for adults with a BMI of 35 or above (or 30 to 34.9 in specific circumstances) alongside at least one weight-related comorbidity. Waiting lists for those specialist services are long in most areas. Private prescribing through a regulated pharmacy allows people who meet the licensed criteria to access treatment without joining that queue, subject to clinical approval. Seeing the cost context for that route is covered on our treatment overview.

If you are exploring whether semaglutide for weight loss could be right for you, a conversation with a prescriber is the right starting point. The medicine is well-studied. Whether it suits your individual health picture is a clinical question, not one a search engine or this page can settle.

Side effects and what to watch for

The side-effect profile is dominated by gastrointestinal symptoms: nausea, loose stools, constipation, indigestion and occasional vomiting. These are most noticeable after starting or after a dose step-up, and they tend to ease as the body adjusts, often within a couple of weeks. Starting at the lowest dose and titrating slowly is how the licensed schedule is designed; the escalation exists specifically to reduce this burden.

A small number of people experience more significant effects. Acute pancreatitis is a known but infrequent possibility. The MHRA highlighted it in a Drug Safety Update in January 2026: persistent, severe stomach pain that reaches through to the back (with or without vomiting) warrants urgent medical attention. Gallbladder problems and, rarely, allergic reactions have also been reported. Patients and healthcare professionals can log any suspected side effects via the MHRA Yellow Card scheme.

Semaglutide is not recommended during pregnancy, while breastfeeding or when actively trying to conceive. It is not licensed for anyone under 18. People with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2 should not use it. Researchers have also investigated whether semaglutide crosses the blood-brain barrier, which helps explain some of the appetite and craving effects people notice beyond simple stomach fullness. These are the kinds of factors a prescriber explores during a consultation, there is no shortcut that replaces that assessment. Our guide to using Wegovy covers the practical side once treatment is underway.