GLP-1 comparison
Mounjaro vs Ozempic
Different companies, different molecules, different receptors. Both are once-weekly injections approved for type 2 diabetes — and in the head-to-head trial, one produced meaningfully more A1C reduction and weight loss than the other.
Mounjaro
Tirzepatide — dual GIP + GLP-1
Two mechanisms in one molecule. In SURPASS-2, produced ~2× the weight loss and greater A1C reduction versus semaglutide 1 mg. Goes up to 15 mg.
Ozempic
Semaglutide — GLP-1 only
Longer real-world track record, cardiovascular outcomes data (SUSTAIN-6), and typically easier US coverage. Caps at 2.0 mg for T2D.
Side by side
Mounjaro
Tirzepatide, Eli Lilly
Ozempic
Semaglutide, Novo Nordisk
Highlighted cells indicate the clearer choice on that row. Sourced from FDA prescribing information and pivotal trials — see references below.
How much would you lose on each?
Project your expected weight loss on tirzepatide or semaglutide from your own weight and dose.
Which one is right for you?
You want the strongest A1C and weight response
SURPASS-2 favored tirzepatide (Mounjaro). If your A1C is high, or weight loss matters alongside diabetes control, Mounjaro is where the head-to-head evidence points.
You want proven cardiovascular protection
Semaglutide (Ozempic) has SUSTAIN-6 data showing a 26% relative reduction in major cardiovascular events in high-risk T2D. Tirzepatide's CV outcome trial is still enrolling.
Cost or coverage is the deciding factor
Both list around $1,000–$1,070 monthly. Coverage varies by plan; some cover one but not the other. Confirm coverage before you commit.
Related in your GLP-1 journey
Full GLP-1 hub →Frequently Asked Questions
Common questions and answers about this calculator.
Is Mounjaro the same as Ozempic?
No. They are different drugs from different companies. Mounjaro is tirzepatide made by Eli Lilly and acts on two receptors (GIP and GLP-1). Ozempic is semaglutide made by Novo Nordisk and acts on GLP-1 only. Both are approved for type 2 diabetes and both are once-weekly subcutaneous injections, but they are separate molecules.
Which is better for weight loss, Mounjaro or Ozempic?
In the SURPASS-2 head-to-head trial in adults with type 2 diabetes, tirzepatide 15 mg produced greater average weight loss (about 11.2 kg) than semaglutide 1 mg (about 5.7 kg) over 40 weeks. For weight loss specifically, the weight-management sibling brands — Zepbound (tirzepatide) and Wegovy (semaglutide) — are the on-label choices; using Mounjaro or Ozempic for weight loss is off-label.
Which lowers A1C more?
Head-to-head, tirzepatide 15 mg lowered A1C by about 2.30 percentage points versus 1.86 for semaglutide 1 mg in SURPASS-2. Across trials, tirzepatide has consistently produced greater A1C reductions than semaglutide at the doses studied. Individual response varies with baseline A1C, adherence, and other diabetes therapies.
Do they have the same side effects?
The side-effect profiles are similar because both slow gastric emptying and act on GLP-1. Nausea, vomiting, diarrhea, constipation and decreased appetite are common with both, and both carry an FDA boxed warning about the risk of thyroid C-cell tumors and are contraindicated in people with a personal or family history of medullary thyroid carcinoma or MEN 2. The rate of gastrointestinal side effects tends to be similar between the two.
Which is cheaper?
US list prices are close — roughly $1,000 for Ozempic and $1,070 for Mounjaro for a 28-day supply. What you actually pay depends on insurance coverage and manufacturer savings cards. Because both are approved for type 2 diabetes, insurance coverage is generally better than for the weight-loss siblings (Wegovy, Zepbound).
Can I switch between them?
Switching between GLP-1 medications is possible but should be planned with your prescriber. Because the two drugs have different maximum doses and titration schedules, your clinician will typically restart titration at a low dose rather than converting units one-for-one. Do not attempt to convert on your own.
Sources
- Mounjaro (tirzepatide) Prescribing InformationU.S. Food & Drug Administration (FDA). 2024.
- Ozempic (semaglutide) Prescribing InformationU.S. Food & Drug Administration (FDA). 2025.
- Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes (SURPASS-2)Frías JP, Davies MJ, Rosenstock J, et al. N Engl J Med. 2021;385(6):503–515. doi:10.1056/NEJMoa2107519
- Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes (SUSTAIN-6)Marso SP, Bain SC, Consoli A, et al. N Engl J Med. 2016;375(19):1834–1844. doi:10.1056/NEJMoa1607141
Tool Information
August 5, 2026
Dr. Jaydeep Sanghani
Meet Akabari
Dr. Jaydeep Sanghani
MBBS, MD, DNB(Anaesth.), PDCC(CCM), DrNB(CCM)
AIIMS Bhubaneswar · AIIMS Rishikesh
Critical care specialist and anesthesiologist with advanced training from AIIMS. Reviews health calculators at Calqulate to ensure medical accuracy and evidence-based standards.