Ozempic vs Mounjaro
Last reviewed against the current FDA prescribing information for both products. Not medical advice.
Short answer
Ozempic and Mounjaro are both once-weekly injections FDA-approved for type 2 diabetes, and neither is FDA-approved for weight management. The main difference is the medicine inside: Ozempic is semaglutide, a GLP-1 receptor agonist, while Mounjaro is tirzepatide, which acts on both GIP and GLP-1 receptors.
Their other approved uses differ. Ozempic is also approved to lower cardiovascular risk in adults with type 2 diabetes and established heart disease, and to lower the risk of kidney decline in adults with type 2 diabetes and chronic kidney disease. Mounjaro is also approved to lower cardiovascular risk in adults with type 2 diabetes at high risk, and for children 10 and older with type 2 diabetes.
If weight management is the goal, the same two medicines are sold for that use as Wegovy (semaglutide) and Zepbound (tirzepatide). Which option suits you depends on your health history, other medicines, coverage and how you tolerate the dose steps, so it is a decision to make with your prescriber.
Key differences
- Active ingredient: semaglutide (Ozempic) vs tirzepatide (Mounjaro).
- Starting dose: 0.25 mg (Ozempic) vs 2.5 mg (Mounjaro). The numbers are not comparable across different molecules.
- Maximum dose: 2 mg weekly (Ozempic) vs 15 mg weekly in adults (Mounjaro).
- Devices: Ozempic comes in multi-dose pens (needles included) or single-dose syringes; Mounjaro comes in single-dose pens, vials and 4-dose KwikPens.
- Children: Mounjaro is approved for type 2 diabetes from age 10; Ozempic’s label covers adults only.
Ozempic and Mounjaro side by side
| From the FDA label | Ozempic | Mounjaro |
|---|---|---|
| Active ingredient | semaglutide | tirzepatide |
| Drug class | GLP-1 receptor agonist | GIP receptor and GLP-1 receptor agonist |
| Manufacturer | Novo Nordisk | Eli Lilly |
| FDA-approved uses |
|
|
| Approved for weight management? | No | No |
| How it's taken | Injection under the skin (subcutaneous) | Injection under the skin (subcutaneous) |
| How often | Once weekly | Once weekly |
| Starting dose | 0.25 mg once weekly for 4 weeks | 2.5 mg once weekly |
| Dose increases | Then 0.5 mg once weekly. If more blood sugar control is needed, the dose can go up to 1 mg, then 2 mg, each after at least 4 weeks on the current dose | If more blood sugar control is needed, increase in 2.5 mg steps after at least 4 weeks on the current dose |
| Maintenance dose | 0.5 mg, 1 mg or 2 mg once weekly (1 mg for the chronic kidney disease indication) | No single maintenance dose in the label; the dose is raised in 2.5 mg steps only if more blood sugar control is needed |
| Maximum dose | 2 mg once weekly | 15 mg once weekly in adults; 10 mg once weekly in children |
| When to take it | Same day each week, any time of day, with or without meals. The injection day can be changed if the last dose was at least 2 days (48 hours) earlier | Any time of day, with or without meals. The injection day can be changed if doses are at least 3 days (72 hours) apart |
| Pens and devices | Multi-dose pens (0.25/0.5 mg, 1 mg and 2 mg dose pens) with NovoFine Plus needles included, and single-dose prefilled syringes (0.25 mg, 0.5 mg, 1 mg) | Single-dose pens, single-dose vials, 4-dose vials and 4-dose KwikPens, each in 2.5, 5, 7.5, 10, 12.5 and 15 mg strengths |
| Storage | Before first use: refrigerate. After first use, a pen can be kept at room temperature (59–86°F) or in the fridge for 56 days. Do not freeze | Refrigerate. Single-dose pens and vials can be kept unrefrigerated (up to 86°F) for a total of 21 days. KwikPens and multi-dose vials: throw away after 30 days at room temperature, 30 days after first use or 4 weekly doses, whichever comes first. Do not freeze |
| Weight results in the label | None: not a weight-management product | None: not a weight-management product |
| Most common side effects (≥5%) | Nausea, Vomiting, Diarrhea, Abdominal pain, Constipation | Nausea, Diarrhea, Decreased appetite, Vomiting, Constipation, Indigestion (dyspepsia), Abdominal pain |
| Boxed warning | Risk of thyroid C-cell tumors. Do not use if you or a family member have had medullary thyroid carcinoma (MTC) or if you have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). | Risk of thyroid C-cell tumors. Do not use if you or a family member have had medullary thyroid carcinoma (MTC) or if you have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). |
| First FDA approval | December 5, 2017 | May 13, 2022 |
Side effects listed are the label's “most common adverse reactions”; the full label also covers serious risks such as pancreatitis, gallbladder problems and low blood sugar. Weight results come from separate placebo-controlled trials and are not a head-to-head comparison unless stated.
Good to know
- Ozempic injection is not FDA-approved for weight management. The weight-management semaglutide product is Wegovy.
- Semaglutide is also sold as a once-daily tablet under the Ozempic and Rybelsus names, which has its own label. This page covers the weekly injection.
- Mounjaro is not FDA-approved for weight management. The weight-management tirzepatide product is Zepbound.
Questions to ask your prescriber
- Which of these is approved for my diagnosis, and is it covered by my plan?
- How should I step up the dose, and what should I do if the side effects are hard to tolerate?
- Do any of my other medicines, or my personal or family history, rule one of these out?
- If I switch from one to the other, what dose should I start on and when?
Sources
- Ozempic (semaglutide) injection — FDA prescribing information, DailyMed (label effective June 1, 2026, version 20) (Sections 1, 2, 3, 6, 16, boxed warning, Instructions for Use; checked September 24, 2026)
- Drugs@FDA: NDA 209637 (Ozempic injection) (Original approval date; checked September 24, 2026)
- Rybelsus / Ozempic (oral semaglutide) tablets — FDA prescribing information, DailyMed (Existence of the Ozempic tablet; checked September 24, 2026)
- Mounjaro (tirzepatide) injection — FDA prescribing information, DailyMed (label effective August 27, 2026, version 40) (Sections 1, 2, 3, 6, 12.1, 16, boxed warning; checked September 24, 2026)
- Drugs@FDA: NDA 215866 (Mounjaro) (Original approval date; checked September 24, 2026)
How we review: every fact on this page is taken from the current FDA prescribing information on DailyMed or from Drugs@FDA, and re-checked on the date shown. This page was reviewed against FDA labeling, not by a named clinician.
Medical disclaimer: This page is general information, not medical advice, diagnosis or treatment, and it doesn't cover every use, dose, warning or side effect. Always follow the advice of your doctor, pharmacist or other prescriber and read the Medication Guide that comes with your medicine. If you think you are having a medical emergency, call your local emergency number. ShotWise is a tracking app and does not prescribe, sell or recommend any medication.
