No. Wegovy is semaglutide, not tirzepatide. Tirzepatide is a different drug, sold as Zepbound for weight management and Mounjaro for type 2 diabetes. Both Wegovy and Zepbound are once-weekly shots for weight management, which is why they get confused. In the one head-to-head trial, SURMOUNT-5, tirzepatide cut body weight by 20.2% versus 13.7% for semaglutide over 72 weeks. If you are new to the drug, read our tirzepatide guide first.
Key takeaways
- Wegovy and Ozempic contain semaglutide. Zepbound and Mounjaro contain tirzepatide. Two molecules, four brand names.
- Semaglutide acts on the GLP-1 receptor; tirzepatide acts on the GLP-1 and GIP receptors.
- SURMOUNT-5: tirzepatide -20.2% versus semaglutide -13.7% at 72 weeks in adults with obesity without diabetes.
- SURPASS-2: in type 2 diabetes, tirzepatide beat semaglutide 1 mg on A1c and weight at every dose.
- Compounded semaglutide and compounded tirzepatide are not FDA approved and are not interchangeable with Wegovy, Ozempic, Zepbound or Mounjaro.
Which drug is in which brand?
This is the whole confusion in one table. Two companies make two molecules, and each molecule is sold under two names depending on the labeled use.
| Brand | Molecule | Receptors | Labeled use |
|---|---|---|---|
| Wegovy | Semaglutide. | GLP-1. | Chronic weight management. |
| Ozempic | Semaglutide. | GLP-1. | Type 2 diabetes. |
| Zepbound | Tirzepatide. | GLP-1 and GIP. | Chronic weight management; moderate to severe obstructive sleep apnea in adults with obesity. |
| Mounjaro | Tirzepatide. | GLP-1 and GIP. | Type 2 diabetes. |
Source: Zepbound and Mounjaro prescribing information (DailyMed) for the tirzepatide rows; Wegovy and Ozempic rows state the active ingredient and general labeled use only.
So: is Wegovy semaglutide or tirzepatide? Semaglutide. Is Zepbound a semaglutide or tirzepatide? Tirzepatide. Is Mounjaro semaglutide or tirzepatide? Tirzepatide. Is Wegovy tirzepatide? No.
Tirzepatide vs Wegovy for weight loss: SURMOUNT-5
SURMOUNT-5 is the trial that compared the two weight management drugs head to head. Adults with obesity and without diabetes took tirzepatide or semaglutide for 72 weeks, along with diet and exercise counseling.
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Try the BMI Calculator →| SURMOUNT-5 (72 weeks, obesity without diabetes) | Tirzepatide (Zepbound) | Semaglutide (Wegovy) |
|---|---|---|
| Mean change in body weight | -20.2% | -13.7% |
Source: SURMOUNT-5, Aronne et al., NEJM 2025.
That is a real difference on average, and it is the main reason people ask about switching. Two things keep it in proportion. Semaglutide's 13.7% is still large; tirzepatide's own placebo arm in SURMOUNT-1 lost only 3.1%. And averages hide spread: some people lose more on semaglutide than the tirzepatide average, and some lose less on tirzepatide than the semaglutide average.
Tirzepatide vs Mounjaro for weight loss
Mounjaro is tirzepatide, so this is not a comparison of two drugs. It is a question about labels. Mounjaro is labeled for type 2 diabetes; Zepbound is labeled for weight management. The molecule does not change with the name, and the weight loss seen in the diabetes trials shows that. In SURMOUNT-2, adults with obesity and type 2 diabetes lost 12.8% at 10 mg and 14.7% at 15 mg over 72 weeks, versus 3.2% on placebo. People with diabetes tend to lose less than people without it in these trials, which is why the SURMOUNT-2 numbers are lower than the SURMOUNT-1 numbers for the same drug.
Compare Ozempic to Mounjaro: the diabetes brands
For the diabetes products, SURPASS-2 is the head-to-head trial: tirzepatide versus semaglutide 1 mg over 40 weeks in adults with type 2 diabetes.
| SURPASS-2 arm (40 weeks) | A1c change (percentage points) | Weight change (kg) |
|---|---|---|
| Tirzepatide 5 mg | -2.01 | -7.6 |
| Tirzepatide 10 mg | -2.24 | -9.3 |
| Tirzepatide 15 mg | -2.30 | -11.2 |
| Semaglutide 1 mg | -1.86 | -5.7 |
Source: SURPASS-2, Frias et al., NEJM 2021.
GLP-1 vs Mounjaro: what the second receptor means
People sometimes say "GLP-1 vs tirzepatide" as if tirzepatide were not a GLP-1 drug. It is. Tirzepatide activates the GLP-1 receptor, and it also activates the GIP receptor. GIP stands for glucose-dependent insulinotropic polypeptide, a second gut hormone. Semaglutide activates GLP-1 only. Both drugs lower appetite, slow stomach emptying, and boost insulin release when blood sugar is high. The second receptor is the current explanation for tirzepatide's larger average weight loss, though the trials measured outcomes rather than mechanism.
Side effects and warnings
The two families share a side effect profile because they share a pathway. The Zepbound label lists nausea, diarrhea, vomiting, constipation, abdominal pain, dyspepsia, injection site reactions, fatigue, hypersensitivity reactions, burping, hair loss and reflux as the most common adverse reactions. Both drug labels carry a boxed warning about thyroid C-cell tumors seen in rats. In SURMOUNT-1, nausea affected 24.6% to 33.3% of people on tirzepatide versus 9.5% on placebo, and stomach effects were mostly mild to moderate and mostly during dose increases. We do not print Wegovy side effect rates because the Wegovy label is not in our verified list.
Difference between Wegovy and tirzepatide in dosing
Tirzepatide starts at 2.5 mg once weekly for 4 weeks, then rises in 2.5 mg steps after at least 4 weeks on each dose, to a maximum of 15 mg. Wegovy semaglutide is titrated from 0.25 mg weekly to a 2.4 mg weekly maintenance dose. The milligrams are not comparable across the two drugs, and no one should convert a dose from one to the other. The Zepbound label says coadministration with any GLP-1 receptor agonist is not recommended, so switching means stopping one and starting the other under a prescriber's plan.
Price
Wegovy prices are not printed here because they are not in our verified list. Zepbound vials through LillyDirect self-pay cost $299 a month at 2.5 mg, $399 at 5 mg, $499 at 7.5 mg and $699 at 10, 12.5 and 15 mg; with commercial coverage and the savings card, as little as $25. FormBlends compounded tirzepatide is $149 for the first month, then $239 a month, or $214 with Subscribe & Save. FormBlends compounded semaglutide is $99 for the first month, then $190, or $165 with Subscribe & Save. See pricing for plans.
What this means for compounded tirzepatide
If you are comparing compounded semaglutide with compounded tirzepatide, the branded trials above are the best guide to what the molecules do, but the compounded products themselves have no trial data. Compounded semaglutide and compounded tirzepatide are not FDA approved and are not interchangeable with Wegovy, Ozempic, Zepbound or Mounjaro. A licensed provider decides whether either is appropriate for you; the assessment is where that decision is made.
Frequently Asked Questions
Is Wegovy tirzepatide?
No. Wegovy is semaglutide, a GLP-1 receptor agonist. Tirzepatide is a dual GIP and GLP-1 receptor agonist sold as Zepbound and Mounjaro.
Is Zepbound a semaglutide or tirzepatide?
Tirzepatide. Zepbound is Eli Lilly's tirzepatide product for chronic weight management and for obstructive sleep apnea in adults with obesity.
Is Mounjaro semaglutide or tirzepatide?
Tirzepatide. Mounjaro is the tirzepatide product labeled for type 2 diabetes. Ozempic is the semaglutide product for the same use.
Tirzepatide vs Wegovy: which is better for weight loss?
On average, tirzepatide. In SURMOUNT-5, tirzepatide produced 20.2% mean weight loss versus 13.7% for semaglutide at 72 weeks. Individual results vary, and tolerance, coverage and your prescriber's judgment all matter.
What is the difference between Wegovy and tirzepatide?
Different molecules and different receptor targets. Wegovy's semaglutide acts on GLP-1; tirzepatide acts on GLP-1 and GIP. Both are weekly injections for weight management with similar stomach side effects and the same boxed thyroid warning.
Sources
- Tirzepatide as Compared with Semaglutide for the Treatment of Obesity (SURMOUNT-5), Aronne et al., New England Journal of Medicine, 2025.
- Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes (SURPASS-2), Frias et al., New England Journal of Medicine, 2021.
- Tirzepatide once weekly for the treatment of obesity in people with type 2 diabetes (SURMOUNT-2), Garvey et al., The Lancet, 2023.
- Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1), Jastreboff et al., New England Journal of Medicine, 2022.
- Zepbound (tirzepatide) prescribing information, DailyMed, National Library of Medicine, revised 08/2026.
- Mounjaro (tirzepatide) prescribing information, DailyMed, National Library of Medicine, revised 08/2026.
- FormBlends pricing, Form Blends LLC, verified September 5, 2026.
Next steps
For the full drug comparison, read semaglutide vs tirzepatide; for the diabetes brands, tirzepatide vs Ozempic; and for the names, what is the brand name for tirzepatide. Browse the tirzepatide hub for every other tirzepatide question. Talk to a clinician before you choose or switch drugs. Compounded tirzepatide is not FDA approved and is not interchangeable with Zepbound or Mounjaro; a licensed provider decides whether it is appropriate for you.
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