Medication · US & Canada
Mounjaro, explained
By Joshua Nichvolodoff · Fact-checked against sources November 2, 2026 · Next review due May 1, 2027
Clinical review: not yet reviewed by a clinician. How review works · Editorial policy
Mounjaro is Eli Lilly's once-weekly tirzepatide injection for type 2 diabetes. It is not FDA-approved for weight management — Zepbound, the same molecule, is[1].
Status in the US and Canada
| Item | United States | Canada |
|---|---|---|
| Type 2 diabetes, adults | Yes | Yes |
| Type 2 diabetes, children | 10 and older | 10 to under 18 |
| Lower risk of major heart events | Yes, in type 2 diabetes at high risk | No |
| Weight management | No (see Zepbound) | No (see Zepbound) |
The heart indication
The US heart indication is based on SURPASS-CVOT. Tirzepatide was shown to be no worse than dulaglutide, another GLP-1 medicine, at preventing heart attacks, strokes and cardiovascular deaths; it was not shown to be better[2][4].
Forms
A once-weekly injection in single-dose pens and vials, multi-dose vials and the KwikPen, in 2.5 to 15 mg strengths[1]. Dose changes follow your prescriber and the label.
The trials behind it
Blood-sugar and heart-outcome trials, with results for both groups, design limits and funding.
Study: SURPASS-2[5]
Does tirzepatide lower blood sugar (HbA1c) more than semaglutide 1 mg in type 2 diabetes treated with metformin?
- Who was in it
- 1,879 adults with type 2 diabetes not controlled on metformin
- What they got
- Tirzepatide 5, 10 or 15 mg once a week
- Compared with
- Semaglutide 1 mg once a week
- How long
- 40 weeks
- What happened
- HbA1c fell 2.01, 2.24 and 2.30 percentage points on tirzepatide 5, 10 and 15 mg vs 1.86 on semaglutide 1 mg. Extra weight loss vs semaglutide: 1.9, 3.6 and 5.5 kg.
- Limits
- Open-label: participants knew which drug they took
- Semaglutide compared at 1 mg, not higher doses approved later
- 40 weeks
- Funded by
- Eli Lilly
Summary by Joshua Nichvolodoff, from the published paper — not written by the study's authors. Clinical review: not yet reviewed by a clinician.
Study: SURPASS-CVOT[4]
Is tirzepatide at least as good as dulaglutide at preventing heart attacks, strokes and cardiovascular deaths in type 2 diabetes with heart disease?
- Who was in it
- 13,299 adults with type 2 diabetes and atherosclerotic cardiovascular disease
- What they got
- Tirzepatide up to 15 mg once a week
- Compared with
- Dulaglutide 1.5 mg once a week (another GLP-1 medicine)
- How long
- Event-driven, multi-year
- What happened
- Heart attack, stroke or cardiovascular death: 12.2% on tirzepatide vs 13.1% on dulaglutide.
- Relative effect
- Hazard ratio 0.92 (95.3% CI 0.83–1.01): non-inferior; superiority not shown
- Limits
- No placebo group — compared with another GLP-1 medicine
- Superiority was not shown
- Funded by
- Eli Lilly
Summary by Joshua Nichvolodoff, from the published paper — not written by the study's authors. Clinical review: not yet reviewed by a clinician.
Related
Tirzepatide · Zepbound · Mounjaro & Zepbound cost · Eating on Mounjaro
General information, not medical advice. Which product and dose is right for you is a decision for you and your prescriber. Light Years earns nothing from any product named here.
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Sources
- MOUNJARO (tirzepatide) injection — prescribing information. U.S. Food and Drug Administration (FDALabel). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/d2d7da5d-ad07-4228-955f-cf7e355c8cc0/spl-doc. Accessed November 2, 2026. Back to the text
- Tirzepatide gets FDA approval to cut cardiovascular risk in type 2 diabetes. HCPLive, August 28, 2026. https://www.hcplive.com/view/tirzepatide-gets-fda-approval-to-cut-cardiovascular-risk-in-type-2-diabetes. Accessed November 2, 2026. Back to the text
- Mounjaro / Mounjaro KwikPen (tirzepatide injection) product monograph. Health Canada Drug Product Database / Eli Lilly Canada, June 23, 2026. https://pdf.hres.ca/dpd_pm/00085122.PDF. Accessed November 2, 2026. Back to the text
- Cardiovascular outcomes with tirzepatide versus dulaglutide in type 2 diabetes (SURPASS-CVOT). New England Journal of Medicine, December 18, 2025. https://pubmed.ncbi.nlm.nih.gov/41406444/ · DOI 10.1056/NEJMoa2505928 · PMID 41406444. Accessed November 2, 2026. Back to the text
- Tirzepatide versus semaglutide once weekly in patients with type 2 diabetes (SURPASS-2). New England Journal of Medicine, August 5, 2021. https://pubmed.ncbi.nlm.nih.gov/34170647/ · DOI 10.1056/NEJMoa2107519 · PMID 34170647. Accessed November 2, 2026. Back to the text
Figures marked “as reported” are historical: they show what the source said on that date, not today's price or rule.
Changes to this page
- — First published.
Substantive corrections are also logged at corrections.