Zepbound vs Mounjaro: Are They the Same?

If you are asking is Zepbound the same as Mounjaro, the short answer is yes — and no. The two are chemically identical: both are tirzepatide, a once-weekly injectable made by Eli Lilly, supplied in the same six dose strengths, carrying the same boxed warning. What differs is the FDA-approved indication on the label — Mounjaro is approved for type 2 diabetes, while Zepbound is approved for chronic weight management and obstructive sleep apnea. Both are FDA-approved prescription drugs, and both are distinct from non-FDA-approved compounded tirzepatide. Below is a clinical breakdown of what is shared and what is not.

Are Zepbound and Mounjaro the same drug?

At the molecular level, yes. Both Zepbound and Mounjaro contain the identical active ingredient tirzepatide, share the same inactive ingredients, and are manufactured by the same company, Eli Lilly; the difference is the FDA-approved indication, not the molecule, according to drug reference data summarizing both brands’ FDA labeling.

Tirzepatide is a once-weekly subcutaneous dual GIP and GLP-1 receptor agonist — the first-in-class single molecule combining both incretin actions (glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1), per a StatPearls pharmacology review. That mechanism is the same whether the box reads “Zepbound” or “Mounjaro.” If you are exploring incretin therapy more broadly, our overview of peptides for weight loss puts tirzepatide in context.

What is the difference between Zepbound and Mounjaro?

The difference is the label. The FDA approved Mounjaro on May 13, 2022 as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes; it is not indicated for type 1 diabetes and is not FDA-approved for chronic weight management, per its FDA approval history. The current Mounjaro prescribing information extends that diabetes indication to pediatric patients 10 years and older.

The FDA approved Zepbound on November 8, 2023 for chronic weight management as an adjunct to a reduced-calorie diet and increased physical activity in adults with obesity or overweight plus a weight-related condition, per Eli Lilly’s announcement. Then, on December 20, 2024, the FDA approved Zepbound as the first prescription medicine for moderate-to-severe obstructive sleep apnea (OSA) in adults with obesity, per a second Lilly release.

Feature	Mounjaro	Zepbound
Active ingredient	Tirzepatide	Tirzepatide
Manufacturer	Eli Lilly	Eli Lilly
FDA approval date	May 13, 2022	Nov 8, 2023 (weight); Dec 20, 2024 (OSA)
FDA-approved indication	Type 2 diabetes glycemic control	Chronic weight management; moderate-to-severe OSA in adults with obesity
Dose strengths	2.5, 5, 7.5, 10, 12.5, 15 mg	2.5, 5, 7.5, 10, 12.5, 15 mg
Route / frequency	Subcutaneous, once weekly	Subcutaneous, once weekly
Boxed warning	Thyroid C-cell tumors	Thyroid C-cell tumors

Both brands come in the same six dose strengths — 2.5, 5, 7.5, 10, 12.5, and 15 mg — as once-weekly subcutaneous injections in single-dose pens or vials, per Medscape dosing reference. For a deeper look at how those strengths are typically titrated, see our tirzepatide dosage chart.

How well does tirzepatide work in clinical trials?

Efficacy depends on the indication and the trial population. These are clinical-trial results by dose and population — not guarantees, and individual results vary.

Weight management (no diabetes): In SURMOUNT-1, a phase 3 double-blind randomized trial of 2,539 adults with obesity or overweight without diabetes, mean body-weight change at week 72 was -15.0% (5 mg), -19.5% (10 mg), and -20.9% (15 mg) versus -3.1% for placebo, per the PubMed record of the NEJM publication.

Type 2 diabetes: In SURPASS-2, an open-label phase 3 trial of 1,879 adults with type 2 diabetes on metformin, HbA1c fell 2.01, 2.24, and 2.30 percentage points for tirzepatide 5/10/15 mg versus 1.86 points for semaglutide 1 mg at 40 weeks, per Healio’s report. Body-weight change in that diabetes trial was -7.6, -9.3, and -11.2 kg versus -5.7 kg for semaglutide 1 mg, per Eli Lilly. Note: these weight numbers are from a diabetes population on metformin, not the obesity indication. (Semaglutide is the drug in Wegovy and Ozempic — a different molecule; the SURPASS-2 comparator was the 1 mg diabetes dose, not Wegovy’s 2.4 mg obesity dose.)

Sleep apnea: In SURMOUNT-OSA, two phase 3 double-blind trials in adults with moderate-to-severe OSA plus obesity, the estimated treatment difference versus placebo in apnea-hypopnea index (AHI) at week 52 was -20.0 events/hour in participants not using PAP (Study 1, n=234) and -23.8 events/hour in those using PAP (Study 2, n=235), per Healio. At the highest dose, 43.0% (Study 1) and 51.5% (Study 2) of participants met trial-defined disease-resolution criteria (AHI under 5, or AHI 5–14 with an Epworth Sleepiness Scale score of 10 or less), per Lilly via PR Newswire. “Met trial-defined resolution criteria” is not the same as a cure.

What are the warnings and side effects?

Because the molecule is identical, the safety profile is the same across both brands. Both Mounjaro and Zepbound carry a boxed warning for the risk of thyroid C-cell tumors — based on rodent studies, with human relevance unknown — and are contraindicated in patients with a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2), per the Lilly prescribing information. The most common adverse effects are gastrointestinal: nausea, diarrhea, vomiting, and constipation. This is educational information, not medical advice — a licensed provider determines whether tirzepatide is appropriate for you.

Is compounded tirzepatide the same as Zepbound or Mounjaro?

No. Zepbound and Mounjaro are FDA-approved branded drugs. Compounded tirzepatide is not FDA-approved; it is compounded, prescription only, and the FDA has not evaluated it for safety, quality, or efficacy. It should never be treated as equivalent to the branded products.

Availability has also tightened. The FDA removed tirzepatide from its drug shortage list in October 2024 and issued a declaratory order on December 19, 2024 confirming the shortage was resolved; the compounding grace periods ran to February 18, 2025 (503A pharmacies) and March 19, 2025 (503B outsourcing facilities), per the FDA. The semaglutide shortage (Ozempic, Wegovy) was separately declared resolved on February 21, 2025, per CNBC. With the shortages over, mass compounding is no longer permitted, and on April 30, 2026 the FDA proposed to exclude semaglutide, tirzepatide, and liraglutide from the 503B bulk drug substances list, per the FDA.

Does insurance cover Zepbound and Mounjaro the same way?

This is where the two brands diverge most for patients. Because Mounjaro is a diabetes drug, it is generally eligible for commercial and Medicare Part D coverage for type 2 diabetes, though plans set their own formularies and do not have to cover every product; verify with your plan, per healthinsurance.org. Zepbound for weight loss, however, runs into Medicare Part D’s longstanding statutory exclusion barring coverage of drugs used for weight loss, so it is generally not covered by Medicare for that purpose — though Medicare may cover Zepbound when it is used for a separately covered indication such as moderate-to-severe OSA.

That gap is not closing soon: in a final rule published in April 2025, CMS opted not to finalize a proposal that would have let Medicare Part D cover anti-obesity medications starting in 2026, so the weight-loss exclusion remains in effect, per the same source. Commercial coverage varies by plan — verify your specific benefits before assuming either drug is covered. Our pricing page explains how telehealth evaluation and self-pay options work.

Frequently asked questions

Is Zepbound the same as Mounjaro?

They are the same active drug, tirzepatide, from the same manufacturer (Eli Lilly), in the same six dose strengths and with the same boxed warning. They are sold as two separately FDA-approved brands with different indications: Mounjaro for type 2 diabetes, Zepbound for chronic weight management and obstructive sleep apnea.

Can I use Mounjaro for weight loss?

Mounjaro is FDA-approved only for glycemic control in type 2 diabetes — it is not FDA-approved for chronic weight management. Zepbound is the tirzepatide brand FDA-approved for weight management. A licensed provider determines which product, if any, is appropriate for you; this is educational information, not medical advice.

Are Zepbound and Mounjaro the same as Ozempic or Wegovy?

No. Zepbound and Mounjaro are tirzepatide (a dual GIP/GLP-1 receptor agonist), while Ozempic and Wegovy are semaglutide — a different molecule. In the SURPASS-2 diabetes trial, tirzepatide was compared against the semaglutide 1 mg diabetes dose, not Wegovy’s 2.4 mg obesity dose.

Is compounded tirzepatide the same as Zepbound or Mounjaro?

No. Compounded tirzepatide is not FDA-approved, is compounded and prescription only, and has not been evaluated by the FDA for safety, quality, or efficacy. Only Zepbound and Mounjaro are FDA-approved tirzepatide products. With the tirzepatide shortage resolved (October 2024) and compounding grace periods ended in early 2025, mass compounding is no longer permitted.

Why is Mounjaro covered by insurance but Zepbound often is not?

Mounjaro is a diabetes medication, so it is generally eligible for commercial and Part D coverage for type 2 diabetes — though plans set their own formularies and do not have to cover every product. Zepbound for weight loss runs into Medicare Part D’s statutory weight-loss exclusion, so it is generally not covered by Medicare for weight loss, though it may be covered for a separately covered indication such as OSA. Coverage varies by plan — verify with yours.

Do Zepbound and Mounjaro have the same side effects?

Because they are the same molecule, yes. Both carry a boxed warning for the risk of thyroid C-cell tumors (based on rodent data, human relevance unknown) and are contraindicated with a personal or family history of medullary thyroid carcinoma or MEN 2. The most common side effects are gastrointestinal: nausea, diarrhea, vomiting, and constipation.