Home / Comparisons / Zepbound vs Mounjaro: Same Drug, Different Labels
Zepbound vs Mounjaro: Same Drug, Different Labels
Zepbound and Mounjaro both contain tirzepatide but have different FDA labels. What each is approved for, the trials that fit each, and the warnings.
On this page
One active ingredient, two products. The difference is on the label: who each is approved for, and which trials fit which label. Brand names are used here only to identify the FDA labels.
Key takeaways
- Zepbound and Mounjaro both contain tirzepatide, a GIP and GLP-1 receptor agonist. They are separate FDA-approved products with separate labels.
- Zepbound’s label covers weight and sleep apnea. It is for reducing and maintaining weight in adults with obesity, or overweight plus a weight-related condition, and for moderate to severe obstructive sleep apnea in adults with obesity.
- Mounjaro’s label covers type 2 diabetes. It is for blood sugar control in adults and children 10 and older, and, since a label change in August 2026, for reducing major cardiovascular events in adults with type 2 diabetes who are at high risk.
- Mounjaro has no weight-loss indication on its label.
- Both carry the same boxed warning for thyroid C-cell tumors seen in rats.
- A compounded version is neither product. FDA does not review compounded drugs for safety, effectiveness or quality before they are marketed.
Are Zepbound and Mounjaro the same drug?
They share the same active ingredient, tirzepatide, but each was approved through its own application (Zepbound, NDA 217806; Mounjaro, NDA 215866) and has its own label.
FDA says that before approval a company must show a drug is safe and effective for its intended uses, and that using an approved drug for an unapproved use is called off-label. So an indication on one label does not carry over to the other. Dosing is set by each label and your prescriber; this guide does not give doses.
What is each one approved for?
✓ means the use is listed on that product’s label as worded. — means it is not.
| Use on the label | Zepbound | Mounjaro |
|---|---|---|
| Reducing excess body weight and maintaining the reduction in adults with obesity, or overweight plus a weight-related condition | ✓ | — |
| Moderate to severe obstructive sleep apnea in adults with obesity | ✓ | — |
| Blood sugar control in type 2 diabetes in adults | — | ✓ |
| Blood sugar control in type 2 diabetes in children 10 and older | — | ✓ |
| Reducing major cardiovascular events in adults with type 2 diabetes at high risk for them | — | ✓ |
Sources: the Zepbound label and the Mounjaro label. The Mounjaro label lists the cardiovascular indication as a change dated August 2026.
Which trials fit which label?
These are randomized trials in people whose characteristics match the labeled uses. Mounjaro’s label names its trials, including SURPASS-2 and SURPASS-CVOT; Zepbound’s label does not name its trials, so for Zepbound we match trials by who was studied. Results are averages. Lilly, which makes tirzepatide, funded the head-to-head trial noted below.
| Label | Trial | Who was studied | What happened |
|---|---|---|---|
| Zepbound: weight | SURMOUNT-1 | 2,539 adults with obesity, or overweight plus a weight-related condition, no diabetes, 72 weeks | Average weight change −15.0% to −20.9% depending on dose arm vs −3.1% on placebo |
| Zepbound: sleep apnea | SURMOUNT-OSA | 469 adults with moderate to severe apnea and obesity, 52 weeks (enrollment) | Apnea-hypopnea index fell 25.3 vs 5.3 events per hour in people not using PAP therapy, and 29.3 vs 5.5 in people using it |
| Mounjaro: heart events | SURPASS-CVOT | 13,299 adults with type 2 diabetes and atherosclerotic cardiovascular disease, compared with dulaglutide | Major cardiovascular events 12.2% vs 13.1% (HR 0.92, 95.3% CI 0.83–1.01). Non-inferior to dulaglutide; superiority was not shown (p=0.09) |
| Mounjaro: blood sugar | SURPASS-2 | 1,879 adults with type 2 diabetes, compared with semaglutide 1 mg, open-label, 40 weeks | HbA1c fell 2.01 to 2.30 points on tirzepatide vs 1.86 on semaglutide. Funded by Lilly |
Points to keep in mind:
- Mounjaro’s cardiovascular indication is new, and its trial result is a non-inferiority result. SURPASS-CVOT did not show that tirzepatide beats dulaglutide on heart events, and we found no trial comparing it with semaglutide on heart events.
- SURPASS-CVOT enrolled people with atherosclerotic cardiovascular disease. The label’s indication is worded for adults with type 2 diabetes at high risk for these events.
- SURPASS-2 also reported weight, but that is not a labeled use of Mounjaro. In that diabetes trial weight differed by 1.9 to 5.5 kg in tirzepatide’s favor. The head-to-head trial in adults with obesity and no diabetes, relevant to Zepbound’s population, is SURMOUNT-5; see our semaglutide vs tirzepatide comparison.
- We did not review the trial behind Mounjaro’s use in children.
Can Mounjaro be used for weight loss, or Zepbound for diabetes?
Neither is a use on that product’s label as worded, which makes it off-label. That is a decision for a prescriber, and we do not recommend either way. FDA’s evaluation of benefits and risks covers the approved use (FDA).
Do they carry the same warnings?
Both labels carry a boxed warning: in rats, tirzepatide caused thyroid C-cell tumors, and it is not known whether either product causes them in humans. Both are contraindicated with a personal or family history of medullary thyroid carcinoma or MEN 2, and with known serious hypersensitivity to tirzepatide.
Both labels list these warnings: acute pancreatitis; low blood sugar (on Mounjaro’s label, with insulin or insulin secretagogues); serious hypersensitivity reactions; acute kidney injury from volume depletion; severe gastrointestinal adverse reactions, and not recommended in severe gastroparesis; diabetic retinopathy complications; acute gallbladder disease; and lung aspiration during general anesthesia or deep sedation (Zepbound label; Mounjaro label). The Zepbound label also says coadministration with other tirzepatide-containing products or with any GLP-1 receptor agonist is not recommended.
Our tirzepatide guide has the full risk details.
Is compounded tirzepatide the same as Zepbound or Mounjaro?
No. FDA says compounded drugs are not reviewed for safety, effectiveness or quality before they are marketed. Tirzepatide does not currently appear on FDA’s 503B bulks list or its drug shortage list (FDA, April 1, 2026). In a Sept. 18, 2026 warning letter, FDA said a tirzepatide-plus-niacinamide product and others appear to be essentially copies of approved drugs. A warning letter is an agency position, not a court ruling. See what FDA says about compounded GLP-1 drugs.
What should you ask your doctor?
- Which label does my reason for treatment fit: weight or sleep apnea, or type 2 diabetes and heart risk?
- If a product is suggested for a use that isn’t on its label, what is the reason and what evidence supports it for me?
- Do I have a personal or family history of medullary thyroid carcinoma or MEN 2? (It rules tirzepatide out.)
- Is the product I am being given the approved one or a compounded one? Who makes it?
We do not give doses, and we do not recommend products, pharmacies or sellers.
Frequently asked questions
Is Zepbound the same as Mounjaro?
They contain the same active ingredient, tirzepatide, but they are separate products with different labels and different approved uses.
Is Mounjaro approved for weight loss?
We found no weight-loss indication on Mounjaro’s label. Zepbound’s label covers weight reduction.
Is Zepbound approved for type 2 diabetes?
We did not find blood sugar control among the uses on Zepbound’s label. Mounjaro’s label covers it.
Does Mounjaro lower the risk of heart attack?
Mounjaro’s label includes an indication for reducing major cardiovascular events in adults with type 2 diabetes at high risk. The trial behind it showed non-inferiority to dulaglutide, not superiority.
Can you take Zepbound and Mounjaro together?
The Zepbound label says coadministration with other tirzepatide-containing products is not recommended. Ask your prescriber about your own situation.
From Best Peptides Today
Sources we checked
- Zepbound prescribing information (DailyMed, rev. 08/2026)FDA. Accessed .
- Mounjaro prescribing information (DailyMed, rev. 08/2026)FDA. Accessed .
- Drugs@FDA: NDA 217806 (Zepbound)FDA. Accessed .
- Drugs@FDA: NDA 215866 (Mounjaro)FDA. Accessed .
- FDA: understanding unapproved use of approved drugs ("off label")FDA. Accessed .
- SURMOUNT-1 trial (PubMed)PubMed. Accessed .
- SURMOUNT-OSA trial (PubMed)PubMed. Accessed .
- SURMOUNT-OSA trial, participant numbers (PubMed)PubMed. Accessed .
- SURPASS-CVOT trial (PubMed)PubMed. Accessed .
- SURPASS-2 trial: tirzepatide vs semaglutide in type 2 diabetes (PubMed)PubMed. Accessed .
- SURMOUNT-5 trial: tirzepatide vs semaglutide (PubMed)PubMed. Accessed .
- FDA clarifies policies for compounders as national GLP-1 supply stabilizesFDA. Accessed .
- FDA warning letter to a compounding pharmacy, Sept. 18, 2026FDA. Accessed .
Written and maintained by the Best Peptides For Editorial Team. How we rate evidence.