What Ozempic actually is
Ozempic is a once-weekly injection containing semaglutide, made by Novo Nordisk. It is licensed in the UK for one thing: treating type 2 diabetes, alongside diet and exercise. It lowers blood sugar, reduces HbA1c, and (because semaglutide mimics the fullness hormone GLP-1) often causes weight loss as a side effect.
That side effect is why Ozempic became a household name. But in the UK, Ozempic has never been licensed for weight management. The semaglutide product licensed for weight loss is Wegovy. The same molecule, at higher doses, in a pen designed for people with obesity rather than diabetes.
Ozempic vs Wegovy: the real difference
| Ozempic | Wegovy | |
|---|---|---|
| Drug | Semaglutide | Semaglutide |
| UK licence | Type 2 diabetes | Weight management (obesity, or overweight with a related condition) |
| Doses | 0.25 mg → 0.5 mg → 1 mg → 2 mg weekly | 0.25 mg → up to 2.4 mg weekly (7.2 mg approved 2026); also a daily tablet |
| Evidence base | SUSTAIN trials (blood sugar, cardiovascular safety in diabetes) | STEP, SELECT, OASIS trials (weight loss, cardiovascular prevention) |
| NICE guidance | Recommended for type 2 diabetes in defined circumstances | TA875 (weight management), TA1152 (cardiovascular risk) |
When Ozempic is prescribed off-label for weight loss, it diverts supply from people with diabetes. The UK has experienced repeated Ozempic shortages for exactly this reason. If you want semaglutide for weight management, the appropriate, licensed product is Wegovy.
Why you should not chase Ozempic for weight loss
Three practical reasons, beyond the licensing technicality:
- Dose ceiling. Ozempic tops out at 2 mg; the weight-management evidence sits at 2.4 mg and above. The dramatic results you have read about come from Wegovy-dose trials, not Ozempic-dose trials.
- Fake pens. Ozempic is the single most counterfeited GLP-1 in the world. The MHRA has seized hundreds of falsified Ozempic pens in the UK. Some contained insulin, which has hospitalised people. Our fake medicines guide shows you the checks.
- Supply ethics. Every off-label Ozempic pen prescribed for weight loss is a pen unavailable to someone with type 2 diabetes who needs it for blood-sugar control.
How Ozempic is dosed (for diabetes)
For its licensed use, Ozempic starts at 0.25 mg once weekly for four weeks (a tolerability dose), then moves to 0.5 mg. If blood sugar needs tighter control, prescribers can increase to 1 mg and, at most, 2 mg weekly. UK pens come in three strengths, each delivering multiple doses. Our Ozempic click calculator breaks down clicks and pen contents for all three.
Side effects in brief
The side-effect profile is the same molecule, so it mirrors Wegovy: nausea, vomiting, diarrhoea and constipation are common early on; acute pancreatitis and gallbladder disease are the rare serious risks the MHRA warns about; and there is a flagged rare risk of NAION (sudden vision loss) with semaglutide. People with diabetes also need to watch for low blood sugar when Ozempic is combined with insulin or sulfonylureas.
Nothing here changes your treatment. You are on the right, licensed product. If weight is also a goal, mention it to your diabetes team; they may discuss whether Wegovy or another option fits your situation better. Do not switch products without them.
Frequently asked questions
Is Ozempic licensed for weight loss in the UK? +
No. Ozempic is licensed only for type 2 diabetes. The semaglutide product licensed for weight management is Wegovy. Prescribing Ozempic for weight loss is off-label, and UK guidance discourages it. Partly because it worsens shortages for people with diabetes.
Is Ozempic the same as Wegovy? +
Same drug (semaglutide), different products. Wegovy comes in higher doses studied specifically for weight management and is licensed for that use; Ozempic is a diabetes medicine with a lower dose ceiling.
Why did everyone call it "the Ozempic craze"? +
Ozempic launched first (2018) and became famous when users reported weight loss. By the time Wegovy (the actual weight-loss version) launched in the UK in 2023, the Ozempic name had already stuck in the media.
Are fake Ozempic pens really a problem? +
Yes. The MHRA has seized hundreds of falsified Ozempic pens in the UK since 2023, and some contained insulin instead of semaglutide, causing hospitalisations. Only ever use GPhC-registered pharmacies, and run through the MHRA #FakeMeds checks before injecting anything.
Can I switch from Ozempic to Wegovy? +
That is a prescriber decision. Because both are semaglutide, switching is clinically straightforward in principle, but doses do not map one-to-one and your medical history matters. Never swap products on your own.
References & official sources
Show all 5 cited sources, with study authors +
- electronic medicines compendium. Ozempic SmPC & patient leaflet: www.medicines.org.uk/emc/search?q=ozempic
- MHRA Drug Safety Update. Ozempic and Saxenda: vigilance required due to potentially harmful falsified products (November 2023): www.gov.uk/drug-safety-update
- NICE. Type 2 diabetes in adults: management (NG28): www.nice.org.uk/guidance/ng28
- NICE TA875. Semaglutide for managing overweight and obesity: www.nice.org.uk/guidance/ta875
- NHS. Type 2 diabetes: www.nhs.uk/conditions/type-2-diabetes/