Mounjaro vs Zepbound: what is the difference, and why is coverage different?
The same medicine, tirzepatide, sold under two brand names for different uses. What each is approved for, what the trials found, who pays, and the published prices.
Written for the United States. Other country versions are coming.
Mounjaro and Zepbound are the same medicine, tirzepatide, in the same doses. Mounjaro is FDA-approved for type 2 diabetes; Zepbound for weight and sleep apnea. That is why plans cover them differently: Medicare drug plans can pay for diabetes use, but the law bars them from paying for weight loss.
Key takeaways
- Mounjaro and Zepbound are both tirzepatide from Eli Lilly, in the same weekly doses of 2.5 mg to 15 mg, but approved for different uses.1,2
- Mounjaro is approved for type 2 diabetes; Zepbound is approved for weight management and for moderate-to-severe sleep apnea in adults with obesity.1,2
- In SURMOUNT-1, people without diabetes lost 20.9% of their weight on Zepbound 15 mg against 3.1% on a dummy injection; 25 to 29 in 100 had nausea.2
- Medicare can cover Mounjaro for diabetes through Part D, but pays for Zepbound for weight only through the temporary GLP‑1 Bridge, and only the KwikPen.5,6
- Lilly lists Zepbound’s self-pay price at $299 to $699 a month by dose for vials or KwikPens, checked October 12, 2026; TrumpRx lists $1,087.10,11
On this page
Are Mounjaro and Zepbound the same medicine?
Yes. Both are tirzepatide, made by Eli Lilly, in the same weekly doses from 2.5 mg to 15 mg. The difference is what each brand is FDA-approved to treat.1,2,3
- GLP‑1 medicines are prescription-only in the US. A licensed prescriber decides whether one fits you.
- Label facts here come from the current US prescribing information (the “label”) for each brand.1,2
- This post compares labels, coverage rules and published prices. It does not rank the brands, and no brand guarantees any result.
- Every risk of these medicines is in our side-effects guide.
Tirzepatide is the medicine; Mounjaro and Zepbound are brand names on the box. It is like acetaminophen sold as Tylenol and under store names: same medicine, different labels. When the FDA approved Zepbound in 2023, it said tirzepatide “is already approved under the trade name Mounjaro” for type 2 diabetes.3
Tirzepatide copies two gut hormones, GIP and GLP‑1, that are released after you eat. Together they help the body release insulin when blood sugar is high, and make you feel full sooner.1
What is each brand approved for?
Mounjaro is for type 2 diabetes. Zepbound is for weight management and for obstructive sleep apnea in adults with obesity.1,2
| Mounjaro | Zepbound | |
|---|---|---|
| Approved uses | Blood-sugar control in type 2 diabetes, adults and children 10 and older. Lowering heart-attack and stroke risk in adults with type 2 diabetes at high risk.1 | Weight loss and keeping it off in adults with obesity, or overweight plus a weight-related condition. Moderate-to-severe sleep apnea in adults with obesity.2 |
| Doses | 2.5 mg to start, rising by 2.5 mg after at least 4 weeks, up to 15 mg (10 mg for children).1 | 2.5 mg to start, rising by 2.5 mg after at least 4 weeks, up to 15 mg.2 |
| Forms | Single-dose pen, single-dose vial, multi-dose vial, 4-dose KwikPen.1 | Single-dose pen, single-dose vial, multi-dose vial, 4-dose KwikPen.2 |
| First US approval | 2022 (label: “Initial U.S. Approval: 2022”).1 | Weight: November 8, 2023. Sleep apnea: December 20, 2024.3,4 |
Because it is the same medicine, the labels warn against using tirzepatide products together. The Zepbound label says giving it with “other tirzepatide-containing products” is not recommended.2
What did the trials find for each use?
In people without diabetes, Zepbound 15 mg lowered weight by 20.9% over 72 weeks, against 3.1% on a dummy injection. In type 2 diabetes the loss was smaller.2
How these trials work:
- People are split at random into groups. One group gets a dummy injection (placebo) with no medicine in it.
- Everyone gets the same diet and activity advice.
- The gap between groups is what the medicine added. A trial average is not a promise: some people lose much more, some very little.
2,539 adults with obesity, or overweight plus a weight-related condition, without diabetes, for 72 weeks. Average start weight 231 lb (104.8 kg). Eli Lilly paid for the trial.2
Weight lost, % of starting weight
For someone starting at 231 lb, 20.9% is about 48 lb (22 kg), by our arithmetic.
938 adults with type 2 diabetes and a BMI of 27 or more, for 72 weeks.2
Weight lost, % of starting weight
1,879 adults with type 2 diabetes already on metformin, for 40 weeks. No dummy group: both arms got an active medicine.1
Weight change, lb (kg)
HbA1c (average blood sugar over about 3 months) fell 2.0 to 2.3 points on Mounjaro against 1.9 on semaglutide.1
These trials had different people, lengths and comparisons, so their numbers can’t be set side by side. SURPASS-2 compared Mounjaro with semaglutide 1 mg, a diabetes dose, not with the Wegovy weight dose.1
- Stomach effects are the most common. In the Zepbound weight trials, 25 to 29 in 100 felt sick (nausea) against 8 in 100 on the dummy injection.2
- Stopping for side effects: 4.8% to 6.7% stopped Zepbound because of side effects, against 3.4% on the dummy injection.2
- Pancreatitis (inflammation of the pancreas) and gallbladder problems are label warnings. Stop and seek advice if pancreatitis is suspected.2
- Low blood sugar is more likely when used with insulin or a sulfonylurea, a common diabetes pill.1
- The birth-control pill may work less well. The label advises a non-oral method, or adding a barrier method, for 4 weeks after starting and after each dose increase.2
- Thyroid tumors were seen in rats. Both brands carry a boxed warning and are not used with a personal or family history of medullary thyroid cancer or MEN 2.1,2
Why does coverage differ when the medicine is the same?
Because US plans pay by approved use. Medicare drug plans can pay for diabetes and sleep apnea uses, but Medicare is barred by law from paying for weight loss.5
KFF, a health-policy research group, says Medicare “has been prohibited by law from covering medications when used specifically for weight loss.” Part D plans can cover GLP‑1s for other approved uses, like type 2 diabetes or sleep apnea.5
| Who pays | Mounjaro (type 2 diabetes) | Zepbound |
|---|---|---|
| Medicare Part D | Can be covered for its approved diabetes uses.5 | Can be covered for sleep apnea. Not for weight.5 |
| Medicare GLP‑1 Bridge (Jul 1, 2026, to Dec 31, 2027) | Not part of the Bridge.6 | KwikPen only, for weight, $50 a month if you meet the rules. Single-dose pens and vials are not covered.6,13 |
| Medicaid | Coverage required for diabetes drugs.7 | Required for sleep apnea since December 2024; weight is a state choice.7 |
Lilly’s own Mounjaro savings card also follows the label. It needs “a prescription for an approved use consistent with FDA-approved product labeling”, and excludes Medicare, Medicaid and other government plans.8
What about Mounjaro for weight without diabetes? That would be “off-label”: a use the FDA has not approved for that brand. The FDA says prescribers “generally may prescribe” a drug off-label when they judge it medically appropriate.9 Whether a plan or savings program pays is a separate question, set by its own rules.8
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What do they cost without insurance?
TrumpRx shows Zepbound’s list price as $1,087 a month. Lilly’s own self-pay price for Zepbound vials or KwikPens runs from $299 to $699 a month by dose.10,11
We checked Lilly’s published self-pay prices for Zepbound on October 12, 2026. A “month” is one KwikPen or four single-dose vials:11
- 2.5 mg: $299 a month.
- 5 mg: $399 a month.
- 7.5 mg to 15 mg: $449 a month if each refill is bought within 45 days of the last one; otherwise $499 for 7.5 mg and $699 for 10 to 15 mg.
We could not open Lilly’s Mounjaro list-price page, and we found no Lilly self-pay price for Mounjaro on its savings page, so we give none.8 We leave out savings-card prices because they depend on your insurance.
Questions people ask
Is Mounjaro the same as Zepbound?
Yes. Both contain tirzepatide, made by Eli Lilly, in the same doses. Mounjaro is approved for type 2 diabetes; Zepbound for weight management and sleep apnea.1,2,3
Can Mounjaro be prescribed for weight loss?
Using Mounjaro for weight without diabetes would be off-label. The FDA says prescribers generally may prescribe off-label when they judge it medically appropriate; plans set their own payment rules.9
Does Medicare cover Zepbound?
Part D plans can cover it for sleep apnea. For weight, only the Medicare GLP‑1 Bridge pays, from July 2026 to December 2027, and only for the KwikPen.5,6
Which is stronger, Mounjaro or Zepbound?
Neither. They are the same medicine with the same doses, 2.5 mg to 15 mg a week. The trial results differ because the people studied differ.1,2
How much is Zepbound without insurance?
Lilly’s self-pay price for vials or KwikPens is $299 to $699 a month depending on dose, checked October 12, 2026.11
How we researched this
On October 12, 2026, we read the current US Mounjaro and Zepbound labels, the FDA’s 2023 and 2024 Zepbound press releases, CMS’s Bridge prescriber sheet, two KFF briefs and Lilly’s published price and savings pages.
All trials here were paid for by Eli Lilly, which makes both brands. Prices are the list price on TrumpRx and Lilly’s published self-pay prices; we left out savings-card prices and name no pharmacy or telehealth service. We could not open Lilly’s Mounjaro list-price page.
Before you move on
- Mounjaro and Zepbound are the same medicine, tirzepatide, in the same doses.
- Mounjaro is approved for type 2 diabetes; Zepbound for weight and sleep apnea.
- Coverage follows the approved use, so the same medicine can be covered under one brand and not the other.
- The Medicare Bridge pays for Zepbound for weight only as the KwikPen.
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Sources
- Eli Lilly. Mounjaro (tirzepatide) injection: US prescribing information, revised 08/2026. pi.lilly.com
- Eli Lilly. Zepbound (tirzepatide) injection: US prescribing information, revised 08/2026. pi.lilly.com
- FDA. FDA approves new medication for chronic weight management. Press release, November 8, 2023. fda.gov
- FDA. FDA approves first medication for obstructive sleep apnea. Press release, December 20, 2024. fda.gov
- KFF. What to know about the BALANCE Model for GLP‑1s in Medicare and Medicaid and the Medicare GLP‑1 Bridge. Updated May 11, 2026. kff.org
- Centers for Medicare & Medicaid Services (CMS). Medicare GLP‑1 Bridge: information for prescribers. CMS Product No. 12235, June 2026. cms.gov
- KFF. Medicaid coverage of and spending on GLP‑1s. January 16, 2026. kff.org
- Eli Lilly. Mounjaro savings and support: savings card terms, CMAT-31122 08/2026, opened October 12, 2026. mounjaro.lilly.com
- FDA. Understanding unapproved use of approved drugs "off label". Content current as of February 5, 2018. fda.gov
- TrumpRx.gov (US government price-listing site). GLP‑1 listings with "original price", opened October 12, 2026. trumprx.gov
- Eli Lilly. Zepbound coverage and savings (self-pay prices for single-dose vials and KwikPen), CMAT-22250 08/2026, opened October 12, 2026. zepbound.lilly.com
- Poison Control (National Capital Poison Center). Opened October 12, 2026. poison.org
- CMS. Medicare GLP‑1 Bridge. Page last modified July 13, 2026. cms.gov
- Eli Lilly. Mounjaro Medication Guide, US. Opened October 12, 2026. pi.lilly.com
Last checked Oct 12, 2026 · Next review due Apr 12, 2027 · Report an error
How this post was made. Written by the GLP Guidebook team from the sources above. It's general information, not medical, legal or tax advice. Talk to a qualified doctor, nurse practitioner or pharmacist before starting, stopping or changing any medicine. How we write