Wegovy and Ozempic contain exactly the same active ingredient, semaglutide, manufactured by the same company, Novo Nordisk. So why are they different products? What distinguishes them? And which one should you be taking for weight loss?
The one-sentence answer
Ozempic is licensed in the UK exclusively for type 2 diabetes. Wegovy is licensed for weight management. In the UK, Ozempic should not be prescribed for weight loss in patients without type 2 diabetes. This is off-label prescribing that previously contributed to medication shortages affecting diabetic patients who depended on it.
Same molecule, different doses, different indications
Both contain semaglutide, a GLP-1 receptor agonist. Both are once-weekly subcutaneous injections. The mechanism is identical. The molecule is identical. What differs is the licensed dose and indication.
Ozempic doses (licensed for type 2 diabetes): starts 0.25mg weekly, escalating to 0.5mg, 1mg, with a maximum of 2mg in some patients.
Wegovy doses (licensed for weight management): starts 0.25mg weekly, escalating through 0.5mg, 1mg, 1.7mg, to a maintenance dose of 2.4mg, with a higher 7.2mg maintenance dose also licensed for adults with obesity who need it.
Wegovy goes up to a higher maintenance dose (2.4mg, and 7.2mg for some adults with obesity) than Ozempic (up to 2mg), and it is Wegovy that was studied and licensed for weight management. At the same dose there is no difference between the two products: semaglutide is semaglutide. The licensed dose and use, not the brand name, are what differ.
Why was Ozempic used for weight loss at all?
Before Wegovy was available in the UK, some clinicians prescribed Ozempic off-label for weight loss after observing significant weight loss in their diabetic patients. Social media amplification, particularly in the US, significantly increased demand. This contributed to major Ozempic shortages in 2022 to 2023, leaving diabetic patients unable to obtain their medication. The MHRA and NHS subsequently advised that Ozempic should be reserved for its licensed indication. Wegovy, developed and licensed specifically for weight management at 2.4mg, is now the appropriate choice.
The clinical evidence for weight loss
STEP-1 trial (Wegovy, semaglutide 2.4mg, NEJM 2021, Wilding JPH et al): average weight loss 14.9% of starting body weight over 68 weeks in adults without diabetes.
Because Wegovy is licensed at a higher dose than Ozempic's typical diabetes dosing, it produces substantially greater weight loss. The dose-response relationship for semaglutide is well established, higher doses produce greater appetite suppression and greater weight reduction. The 2.4mg maintenance dose used in Wegovy is the dose at which the clinical weight loss evidence was generated.
Cardiovascular evidence
Ozempic: In SUSTAIN-6 (New England Journal of Medicine, 2016), a safety trial in 3,297 adults with type 2 diabetes at high cardiovascular risk, 6.6% of people on semaglutide had a heart attack or stroke or died from cardiovascular causes over about two years, compared with 8.9% on placebo. It was designed to show that semaglutide is safe for the heart, not to prove a benefit.
Wegovy: In the SELECT trial (New England Journal of Medicine, 2023), which included 17,604 adults aged 45 or over with established cardiovascular disease, a BMI of 27 or more and no diabetes, 6.5% of people on semaglutide 2.4mg had a heart attack or stroke or died from cardiovascular causes over an average follow-up of 39.8 months, compared with 8.0% on placebo, a 20% lower relative risk. Individual results vary. Wegovy 2.4mg is the only weight-management medicine with a UK licence to reduce the risk of heart attack, stroke and cardiovascular death, for adults with established cardiovascular disease and a BMI of 27 or more.
Can I use Ozempic instead of Wegovy?
In the UK: not appropriately. Without a type 2 diabetes diagnosis, Ozempic is not licensed for you and should not be prescribed for weight loss. Being offered Ozempic for weight loss without a diabetes diagnosis by a private provider is a red flag, the prescribing is off-label, the dose is lower than the evidence for weight management supports, and it diverts supply from diabetic patients.
Which is right for me?
No type 2 diabetes, seeking weight loss: Wegovy is the appropriate licensed option.
Type 2 diabetes, seeking weight loss: either may be appropriate depending on your clinical picture. Wegovy at 2.4mg produces greater weight loss; Ozempic provides proven glycaemic benefit at established diabetes doses. Your prescribing pharmacist or diabetes team will advise.
Cardiovascular disease with obesity or overweight: Wegovy's SELECT trial evidence gives it a specific licensed advantage that Ozempic does not share for non-diabetic patients with cardiovascular disease.
How does Mounjaro compare?
In SURMOUNT-5 (New England Journal of Medicine, 2025), a 72-week trial comparing the two medicines directly in 751 adults with obesity but not diabetes, people on the highest dose they could tolerate of tirzepatide lost an average of 20.2% of their body weight, compared with 13.7% on semaglutide. Individual results vary. SURMOUNT-5 used semaglutide doses up to 2.4mg; no trial has compared Mounjaro with Wegovy 7.2mg.
"Wegovy and Ozempic are the same molecule at different doses for different licensed indications. The weight loss evidence was generated at Wegovy's 2.4mg dose, which is why Wegovy, not Ozempic, is the appropriate choice for weight management in the UK."