Mounjaro vs Ozempic: Which Is Better for Weight Loss and Diabetes?
Mounjaro (tirzepatide) and Ozempic (semaglutide) are both once-weekly injectable medications approved for type 2 diabetes. Many patients use them for weight loss — Mounjaro off-label for weight loss (or as its weight-loss-specific brand Zepbound), and Ozempic off-label (or as its weight-loss brand Wegovy).
In a head-to-head trial (SURPASS-2), Mounjaro produced more weight loss and better blood sugar control than Ozempic at all dose levels.
Side-by-Side Comparison
| Mounjaro | Ozempic | |
|---|---|---|
| Generic name | Tirzepatide | Semaglutide |
| Manufacturer | Eli Lilly | Novo Nordisk |
| FDA approved for | Type 2 diabetes (2022) | Type 2 diabetes (2017) |
| Weight loss brand | Zepbound (approved 2023) | Wegovy (approved 2021) |
| Mechanism | Dual agonist: GLP-1 + GIP | Single agonist: GLP-1 |
| Doses available | 2.5, 5, 7.5, 10, 12.5, 15 mg | 0.25, 0.5, 1, 2 mg |
| Administration | Once-weekly injection (pre-filled pen) | Once-weekly injection (pre-filled pen) |
| List price | ~$1,059/month | ~$935/month |
| Oral option | No | Yes (Rybelsus) |
What Each Drug Is
Mounjaro (Tirzepatide)
Mounjaro is a dual GLP-1/GIP receptor agonist — the first drug in its class to target two incretin hormones simultaneously. It was FDA-approved for type 2 diabetes in 2022. The same molecule is sold as Zepbound specifically for weight loss.
Ozempic (Semaglutide)
Ozempic is a GLP-1 receptor agonist approved for type 2 diabetes since 2017. It is one of the most prescribed diabetes medications worldwide. The same molecule at a higher dose (2.4 mg) is sold as Wegovy for weight loss, and an oral version (Rybelsus) is available for diabetes.
For a detailed molecular comparison, see Tirzepatide vs Semaglutide.
Weight Loss Results
| Drug | Trial | Duration | Weight Loss |
|---|---|---|---|
| Mounjaro 15 mg | SURMOUNT-1 (obesity) | 72 weeks | -22.5% |
| Mounjaro 10 mg | SURMOUNT-1 (obesity) | 72 weeks | -21.4% |
| Mounjaro 5 mg | SURMOUNT-1 (obesity) | 72 weeks | -16.0% |
| Mounjaro (vs Ozempic) | SURPASS-2 (T2D) | 40 weeks | -12.4% (15 mg) |
| Ozempic 1 mg (vs Mounjaro) | SURPASS-2 (T2D) | 40 weeks | -6.2% |
| Wegovy 2.4 mg | STEP 1 (obesity) | 68 weeks | -14.9% |
In the SURPASS-2 head-to-head trial for type 2 diabetes, Mounjaro at all three doses (5, 10, 15 mg) produced more weight loss than Ozempic 1 mg. The highest dose produced roughly twice the weight loss of Ozempic.
Diabetes Management
Both drugs are highly effective for type 2 diabetes, but Mounjaro has shown superior glucose control.
| Outcome | Mounjaro (SURPASS-2) | Ozempic (SURPASS-2) |
|---|---|---|
| HbA1c reduction (max dose) | -2.58% | -1.86% |
| HbA1c below 7.0% | Up to 92% | 81% |
| HbA1c below 5.7% (normal) | Up to 46% | 19% |
| Weight loss | -12.4 kg (15 mg) | -6.2 kg |
Nearly half of patients on Mounjaro 15 mg reached a normal HbA1c (below 5.7%) — an outcome rarely seen with diabetes medications. Ozempic achieved this in 19% of patients.
Their Weight Loss Branded Versions
Both drugs have FDA-approved weight-loss-specific brands:
- Mounjaro → Zepbound (tirzepatide for obesity, approved November 2023)
- Ozempic → Wegovy (semaglutide for obesity, approved June 2021)
The active ingredient is the same — the difference is the indication, dosing, and insurance coverage. For a detailed comparison of the weight loss versions, see Zepbound vs Wegovy.
Side Effects
| Side Effect | Mounjaro (SURPASS-2) | Ozempic (SURPASS-2) |
|---|---|---|
| Nausea | 12-22% | 18% |
| Diarrhea | 12-16% | 12% |
| Vomiting | 2-8% | 8% |
| Decreased appetite | 5-11% | 9% |
| Constipation | 5-7% | 4% |
| Discontinuation (AEs) | 3-7% | 5% |
Both drugs have similar GI side effect profiles. Side effects are most common during dose escalation and typically improve at maintenance doses. Gradual titration is used with both drugs to minimize GI symptoms.
Cost
| Mounjaro | Ozempic | |
|---|---|---|
| List price | ~$1,059/month | ~$935/month |
| Direct pricing | LillyDirect: ~$550/mo | Not available |
| Manufacturer savings | Lilly savings card | Novo savings card |
| Insurance coverage (T2D) | Growing (formulary-dependent) | Broad (established since 2017) |
| Insurance coverage (weight loss) | As Zepbound (growing) | As Wegovy (broader) |
Ozempic has broader insurance coverage for type 2 diabetes due to its longer time on the market. Mounjaro's coverage is growing rapidly. For weight loss, insurance coverage remains challenging for both (as Zepbound and Wegovy respectively).
The Next Generation: Retatrutide
Retatrutide is Eli Lilly's next-generation triple agonist — targeting GLP-1, GIP, and glucagon receptors simultaneously. In Phase 3 trials, it produced 28.7% body weight loss, exceeding both Mounjaro and Ozempic. It is not yet FDA-approved (expected 2027).
Learn more: Retatrutide vs Mounjaro | What Is Retatrutide?
Frequently Asked Questions
Is Mounjaro better than Ozempic for weight loss?
In the SURPASS-2 head-to-head trial, Mounjaro produced approximately twice the weight loss of Ozempic at maximum doses. In the separate SURMOUNT-5 trial (comparing their weight loss versions), tirzepatide produced -20.2% vs semaglutide's -13.7%. For weight loss, the evidence favors Mounjaro/tirzepatide.
Is Mounjaro better than Ozempic for type 2 diabetes?
In SURPASS-2, Mounjaro was superior to Ozempic on both HbA1c reduction and weight loss. Up to 46% of Mounjaro patients achieved a normal HbA1c (below 5.7%) vs 19% on Ozempic. Both are highly effective, but Mounjaro showed stronger results.
Can I take Mounjaro or Ozempic for weight loss without diabetes?
Both have weight-loss-specific brands: Mounjaro is sold as Zepbound and Ozempic as Wegovy for chronic weight management. These are FDA-approved for weight loss in adults with BMI 30+ (or 27+ with weight-related conditions). Some doctors prescribe Mounjaro or Ozempic off-label for weight loss.
How much does Mounjaro cost vs Ozempic?
Mounjaro lists at approximately $1,059/month; Ozempic at approximately $935/month. Lilly offers LillyDirect pricing at ~$550/month. Both manufacturers offer savings cards. Actual out-of-pocket cost depends heavily on insurance coverage.
Does Ozempic come in a pill?
Yes. Semaglutide is available as an oral tablet under the brand name Rybelsus for type 2 diabetes, and as oral Wegovy for weight loss (approved 2025). Mounjaro is currently injection-only.
Sources
- Frías, J.P., et al. (2021). Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes (SURPASS-2). New England Journal of Medicine. DOI: 10.1056/NEJMoa2107519
- Jastreboff, A.M., et al. (2022). Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). New England Journal of Medicine. DOI: 10.1056/NEJMoa2206038
- Wilding, J.P.H., et al. (2021). Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). New England Journal of Medicine. DOI: 10.1056/NEJMoa2032183
Medical Disclaimer
The content on glp3.wiki is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Mounjaro and Ozempic are prescription medications — consult your healthcare provider to determine which is appropriate for you.
This site is not affiliated with Eli Lilly, Novo Nordisk, or any pharmaceutical manufacturer.
Sources
Related reading
Tirzepatide vs Semaglutide: Complete Comparison (2026 Data)
Tirzepatide vs semaglutide with SURMOUNT-5 head-to-head data: -20.2% vs -13.7% weight loss. Full comparison of efficacy, side effects, and access.
Zepbound vs Wegovy: Which Weight Loss Drug Is Better?
Zepbound produced -20.2% vs Wegovy's -13.7% weight loss in the SURMOUNT-5 head-to-head trial. Full comparison of cost, side effects, and CV data.
Retatrutide vs Mounjaro vs Ozempic
How the three generations of weight loss drugs compare — single, dual, and triple agonists.