Mounjaro and Zepbound are the brand names of tirzepatide, both made by Eli Lilly. Compare forms, dosing, and what to know before you ask your doctor.
The brand names of tirzepatide are Mounjaro and Zepbound, and both are made by Eli Lilly. Mounjaro is FDA-approved for type 2 diabetes and Zepbound is FDA-approved for chronic weight management, but the active ingredient in each is identical. No third FDA-approved tirzepatide brand exists in the United States.
What Are the Brand Names of Tirzepatide?
Tirzepatide is a once-weekly injection that activates two gut-hormone receptors, GIP and GLP-1. The tirzepatide brand name a patient receives depends on the condition the prescriber is treating, not on the drug itself.
- Mounjaro — approved by the FDA in May 2022 for adults with type 2 diabetes, used alongside diet and exercise.
- Zepbound — approved in November 2023 for adults with obesity, or with overweight plus at least one weight-related health condition such as high blood pressure or sleep apnea.
Both products use the same molecule, the same single-dose pen, and the same weekly schedule. In Spanish-speaking markets, the tirzepatide nombre comercial is also Mounjaro, so the product name does not change from country to country.
Mounjaro vs. Zepbound: Side-by-Side Comparison
The two brands are chemically the same drug sold under two different labels. The practical differences come down to the approved indication, the packaging, and how insurers cover each one.
| Feature | Mounjaro | Zepbound |
|---|---|---|
| Active ingredient | Tirzepatide | Tirzepatide |
| Manufacturer | Eli Lilly | Eli Lilly |
| FDA-approved use | Type 2 diabetes | Chronic weight management |
| Starting dose | 2.5 mg weekly | 2.5 mg weekly |
| Maximum dose | 15 mg weekly | 15 mg weekly |
| Form | Single-dose pen | Single-dose pen or vial |
Insurance coverage is usually the biggest real-world difference between the two labels. Many plans cover Mounjaro for type 2 diabetes while placing Zepbound on a higher tier or excluding it for weight loss.
Who Makes Brand-Name Tirzepatide?
Eli Lilly and Company is the tirzepatide manufacturer behind both Mounjaro and Zepbound. Eli Lilly is the only company with FDA approval to sell brand-name tirzepatide in the United States.
People searching for tirzepatide Lilly are usually trying to confirm that point, or they are looking for the LillyDirect pharmacy service that ships some brand prescriptions directly to patients. Buying from an unverified online seller raises the risk of receiving counterfeit, expired, or mislabeled product.
Non-compounded tirzepatide vs. compounded tirzepatide
Non compounded tirzepatide means the FDA-approved brand product made in a Lilly facility. Compounded tirzepatide is prepared by a state-licensed pharmacy and is not FDA-approved, so its strength, purity, and salt form (such as tirzepatide acetate) can differ from the brand.
Compounded versions are not interchangeable with Mounjaro or Zepbound, and the FDA has warned about counterfeit and mislabeled vials sold online. If a label lists units instead of milligrams, that is a compounded or research product rather than a brand-name pen.
Dosing, Half-Life, and How Results Are Measured
Mounjaro and Zepbound follow the same schedule: 2.5 mg once weekly for four weeks, then increases of 2.5 mg as tolerated, up to a maximum of 15 mg weekly. The starting dose is a tolerance step, not a treatment dose.
The half life of tirzepatide is about five days, which is why the injection is weekly rather than daily. Steady levels are generally reached after roughly four doses.
A frequent question among patients is simple: do higher doses of tirzepatide increase weight loss? In the SURMOUNT-1 trial, average weight loss did rise as the dose increased, but nausea and vomiting became more common at higher doses, so the maximum dose is not automatically the best one.
Safety and Side Effects
Both brands carry a boxed warning about thyroid C-cell tumors observed in rodents. Tirzepatide is not recommended for people with a personal or family history of medullary thyroid cancer or MEN2 syndrome.
The most common side effects of tirzepatide are nausea, diarrhea, vomiting, constipation, indigestion, and fatigue, and they often ease after a few weeks at a stable dose.
Serious but less common risks include pancreatitis, gallbladder disease, kidney problems caused by dehydration, and low blood sugar when the drug is combined with insulin or a sulfonylurea. Anyone with severe or persistent abdominal pain should seek medical care rather than wait for the next scheduled dose.
How Tirzepatide Compares to Other Medications
Tirzepatide is not the only medication in this class. Semaglutide, sold as Ozempic and Wegovy, targets GLP-1 alone, while tirzepatide targets both GIP and GLP-1.
In head-to-head research, tirzepatide has produced greater average weight loss than semaglutide 2.4 mg. Researchers are also studying cagrilintide vs tirzepatide as part of the next wave of obesity treatments, though those combinations are not yet approved.
Brand-name tirzepatide is a prescription medicine, and treatment decisions should be made with a licensed healthcare professional who can review your medical history, kidney function, and other medications.
Frequently Asked Questions
What are the brand names of tirzepatide?
The two FDA-approved brand names of tirzepatide are Mounjaro and Zepbound, and both are manufactured by Eli Lilly. Mounjaro is approved for type 2 diabetes, while Zepbound is approved for chronic weight management. Both contain the same active ingredient, tirzepatide, and use the same weekly dosing schedule.
Is compounded tirzepatide the same as the brand-name version?
No. Compounded tirzepatide is mixed by a state-licensed pharmacy and is not FDA-approved, so its strength, purity, and salt form can differ from Mounjaro or Zepbound. Compounded products are not interchangeable with the brand, and the FDA has warned about counterfeit and mislabeled vials sold online.
Is there a generic version of tirzepatide in the United States?
No generic tirzepatide is available in the United States. Mounjaro and Zepbound are protected by patents that are expected to run into the 2030s. Compounded tirzepatide is sometimes marketed as a cheaper alternative, but it is not an FDA-approved generic.
This page provides educational research information and does not replace medical advice, diagnosis, or treatment.