Ozempic vs Wegovy
How Ozempic and Wegovy differ on molecule, dose, schedule and what they are licensed for.
Same molecule, different label and ceiling. If the question is which is better, the answer is that they are the same drug — what differs is what they are licensed for and how high the dose goes.
| Ozempic | Wegovy | |
|---|---|---|
| Active ingredient | Semaglutide | Semaglutide |
| Licensed for | Type 2 diabetes; cardiovascular risk reduction in some populations | Chronic weight management; cardiovascular risk reduction in some populations |
| How it is taken | Once weekly, any day, with or without food | Once weekly, any day, with or without food |
| Half-life | ~160 hours (about 7 days) | ~160 hours (about 7 days) |
| Starting dose | 0.25 mg | 0.25 mg |
| Highest dose | 2 mg | 2.4 mg |
| Maintenance | 0.5 mg, 1 mg or 2 mg weekly, depending on response. | 2.4 mg weekly. If that is not tolerated, a prescriber may hold at 1.7 mg. |
| Device | Multi-dose pen, reusable for several weeks | Single-dose pen, one per week |
| In-use window | 56 days | 28 days (US label) or up to 6 weeks (EU label) |
| Late dose allowed | 5 days | 5 days |
The same molecule, twice
Ozempic and Wegovy both contain semaglutide. There is no pharmacological comparison to make: the substance entering your body is identical. What differs is the licence, the dose ceiling, and often the device.
This matters more than it sounds. The licence determines what a prescriber can prescribe it for and what a health system or insurer will fund. The ceiling determines how far the ladder goes. Neither is a property of the drug — both are properties of the paperwork around it, and both are entirely real in terms of what you can actually obtain.
Ozempic
Ozempic is semaglutide, licensed for type 2 diabetes. It is the product that made this class famous, and much of the confusion around GLP-1 medicines traces back to it: the same molecule is also sold as Wegovy® for weight management, at a higher maximum dose and under a different label.
The practical difference between Ozempic and Wegovy is the ceiling. Ozempic tops out at 2 mg weekly; Wegovy goes to 2.4 mg and is licensed for weight management rather than glucose control. The pens are also built differently — an Ozempic pen delivers several doses from one cartridge, which is why the strength is described per dose rather than per pen.
Full Ozempic reference · dosing · side effects
Wegovy
Wegovy is semaglutide licensed for weight management. Same molecule as Ozempic®, different label, higher ceiling, and a different pen: each Wegovy pen holds a single dose and is discarded after use.
The full escalation takes about sixteen weeks, which is longer than most people expect and is the single most common source of early disappointment. The starting dose is not a treatment dose; it exists so your gut can adapt. Judging the medicine at week three is judging it before it has started.
Full Wegovy reference · dosing · side effects
Side effects compared
The honest answer is that the gastrointestinal profile is broadly similar across this whole class, because it comes from the same mechanism: a stomach that empties more slowly. Nausea, early fullness, constipation and reflux appear on every label here.
What differs is intensity, and intensity tracks dose and effect size rather than the specific molecule. A product that produces a larger average metabolic change tends to produce more of the gut effects along with it. Comparing two products at the doses people actually take is therefore more informative than comparing them at their maximums — and both are less informative than your own first two dose increases.
Which is more effective?
Trials give averages, and averages are the right way to compare products and the wrong way to predict an individual. Where head-to-head data exist, they show real differences between molecules — but the spread of individual responses within either arm is wider than the gap between the arms.
What that means in practice: the product with the better trial number is a reasonable starting assumption and a poor guarantee. Plenty of people do better on the one the numbers favour less, and the only way to find out which group you are in is to take one properly — at a maintenance dose, for long enough, with the schedule kept.
Switching between them
Do not switch on your own. Doses are not interchangeable between molecules and there is no conversion factor. Moving across without re-escalating reproduces the worst of a first escalation, at full strength.
A supervised switch normally means starting the new product near the bottom of its own ladder even if you were at the top of the previous one, and accepting a few weeks of reduced effect while levels rebuild. Where the two products share a molecule, the switch is simpler — but it is still a prescribing decision, because the licence and the ceiling change with it.
Availability
Which of these you can actually obtain depends on where you live. Licences differ between regions, brand names differ for identical molecules, and supply has been intermittent across this whole class. A comparison that concludes one product is preferable is of limited use if your pharmacy cannot get it.
Common questions
How long does it take to reach the maintenance dose of Ozempic?
At minimum five weeks to reach 0.5 mg, and a further four weeks for each step after that. Someone going all the way to 2 mg is looking at roughly thirteen weeks. Most people never need the top dose — 0.5 mg and 1 mg are both recognised maintenance doses, and the target is glucose control rather than the highest number on the pen.
Does Ozempic cause hair loss?
Hair shedding is reported, but the mechanism most likely is not the drug itself — it is telogen effluvium, the temporary shedding that follows rapid weight loss or a sharp drop in protein and micronutrient intake. It is usually reversible. Keeping protein intake up is the practical response.
How long does it take to get to the full Wegovy dose?
About sixteen weeks — five doses, four weeks each. This is longer than most people expect and is the most common source of early disappointment. The 0.25 mg starting dose is not a treatment dose; it exists so your gut can adapt.
Does Wegovy cause muscle loss?
Rapid weight loss takes lean tissue with it unless protein intake and resistance training make it not. This is the least discussed and most consequential part of the treatment. We cover the numbers here.
Cost, coverage and supply
Price is frequently the deciding factor and it is the one this site can say least about, because it varies by country, by health system, by insurer and by indication. Two things are worth knowing in general terms.
First, coverage usually follows the licence. A product licensed for diabetes is often funded for diabetes and not for weight management, even when the molecule is identical to one that is. That is why the same substance can be straightforward to obtain under one brand name and difficult under another.
Second, supply across this whole class has been intermittent, and shortages have moved between products rather than affecting all of them at once. A plan that depends on one specific brand being available every month is more fragile than it looks. It is worth asking your prescriber what the alternative would be if your product became unavailable — before it does.
Questions worth asking about this choice
- Which of these is licensed for my indication where I live?
- Which one can you actually obtain reliably at the moment?
- Is there a reason from my history to prefer one over the other?
- If this one does not suit me, what would we try next, and would I have to start the ladder again?
- What would we regard as this having worked, and by when?
That last question is the one people most often leave the room without having asked, and it is the one that prevents a treatment drifting for a year without anyone deciding whether it is working.
A note on sources. The figures in the table come from the manufacturers' approved labelling and from published pharmacokinetic data. Regional labels differ, sometimes materially — where a number matters, the leaflet in your own box outranks anything written here. Our editorial standards set out how these pages are sourced and corrected.
What the choice actually depends on
Not, mostly, on which of these two is better. It depends on your indication, your medical history, what is licensed and funded where you live, what your prescriber can obtain, and which routine you can realistically sustain for a year. A table cannot weigh those.
What a table can do is tell you what you are being offered and what questions to ask about it — which turns a consultation into a shorter and more useful conversation than it would otherwise be.