Medical comparison
Mounjaro vs Ozempic
An honest, science-based comparison of Mounjaro (tirzepatide) and Ozempic (semaglutide). Which suits your situation and what is realistic to expect.
Short conclusion
Mounjaro is on average 1.5 to 2x more effective than Ozempic for weight loss (average 20% vs 12% at maximum dose). Mounjaro acts on two receptors (GLP-1 and GIP), Ozempic on one (GLP-1). However, Mounjaro costs 60 to 80% more per month. For BMI ≥35 or stagnation on Ozempic, Mounjaro is often the next step.
Comparison on 12 points
All relevant criteria that determine the choice between Mounjaro and Ozempic, based on clinical data and the Dutch healthcare situation.
| Criterion | Mounjaro | Ozempic | Winner |
|---|---|---|---|
| Active ingredient | Tirzepatide | Semaglutide | - |
| Mechanism of action | GLP-1 + GIP (dual) | GLP-1 (single) | Mounjaro |
| Administration | 1x weekly injection | 1x weekly injection | Equal |
| Pen system | KwikPen (cartridge) | FlexTouch | Ozempic (simpler) |
| Average weight loss (max dose) | 20-22.5% | 10-12% | Mounjaro |
| Effect on HbA1c (diabetes) | -2.0 to -2.5% | -1.5 to -1.8% | Mounjaro |
| Side effects (% nausea) | ~25% | ~20% | Ozempic (slightly milder) |
| Titration time to max dose | 20 weeks (2.5→15 mg) | 16 weeks (0.25→2 mg) | Ozempic (faster) |
| Monthly price (max dose) | €419 | €185 | Ozempic (€/month) |
| Cost per kg lost | ~€20/kg | ~€18/kg | Equal |
| Reimbursement NL (type 2 diabetes) | Yes | Yes | Equal |
| Reimbursement NL (obesity off-label) | No | No | Equal |
Why is Mounjaro more effective?
The dual mechanism of action is the main reason. Tirzepatide binds to both the GLP-1 receptor (like semaglutide) and the GIP receptor (Glucose-dependent Insulinotropic Polypeptide). This second receptor strengthens three effects:
- Insulin sensitivity improves more strongly, especially in fat tissue
- Resting energy expenditure rises by 2-3% (BMR effect)
- Fat cell differentiation is inhibited, so fewer new fat cells form
In the SURMOUNT-1 study (2,539 patients, 72 weeks), the 15 mg group lost an average of 22.5% of their weight. For comparison: STEP-1 with semaglutide 2.4 mg gave 14.9% loss. Mounjaro also performs better in type 2 diabetes: HbA1c drops 0.5% more than with Ozempic.
When do you still choose Ozempic?
Ozempic is not an outdated alternative — for many patients it is still the first choice. Four situations where Ozempic makes more sense:
1. Limited budget
Ozempic costs around €185 per month at max dose compared with €419 for Mounjaro. A difference of €2,800 per year. For BMI 27-32, Ozempic often delivers sufficient results (~10% weight loss).
2. Milder obesity (BMI 27-32)
The additional effect of Mounjaro is particularly impressive in severe obesity. At a BMI around 30, the difference in absolute kilos is limited and the extra costs weigh more heavily.
3. History of stomach complaints
Mounjaro's dual action is more intense and can cause more nausea during the titration phase. With a sensitive stomach, starting with Ozempic and possibly switching later is more comfortable.
4. Type 2 diabetes with good HbA1c control
If your HbA1c is already below 7% with diabetes medication, the marginal extra effect of Mounjaro is small. Reimbursed Ozempic then remains the logical choice.
Which suits you? Decision tree
Do you have type 2 diabetes and is weight loss your primary goal?
→ Consider Mounjaro — it is reimbursed and more effective.
BMI 35 or higher, no budget constraint?
→ Mounjaro — maximum effect is justified in severe obesity.
BMI 27-32, budget is a factor?
→ Ozempic or Wegovy — comparable results at lower cost.
Stagnation on Ozempic after 6+ months?
→ Switch to Mounjaro — often +5-8% extra weight loss thanks to the GIP component.
Previous severe nausea on GLP-1?
→ Start with Ozempic (lowest dose), evaluate after 3 months whether switching to Mounjaro is possible.
Want the lowest possible costs?
→ Ozempic (off-label) or Wegovy via the GVS route through your GP.
Costs in detail
The pharmacy purchase prices (AIP) as published on medicijnkosten.nl in 2026. The actual price at the counter may differ slightly due to the pharmacy mark-up.
Mounjaro 6 months titration
€1,948
2.5 mg → 15 mg titration. Average €325/month.
Ozempic 6 months titration
€634 – €790
0.25 mg → 1 mg or 2 mg. Average €106-132/month.
The Basic programme at Go Leaner (€199/month, minimum 6 months) comes on top of the medication costs and includes the intake consultation, blood tests, a monthly doctor check-in and lifestyle coaching.
View full costs →Frequently asked questions
What is the difference between Mounjaro and Ozempic?
Mounjaro (tirzepatide) acts on two receptors: GLP-1 and GIP. Ozempic (semaglutide) acts on GLP-1 only. Mounjaro's dual mechanism makes it more effective in clinical studies (~20% versus ~12% weight loss at maximum dose).
Which is better, Mounjaro or Ozempic for weight loss?
For maximum weight loss, Mounjaro is more effective. In SURMOUNT-1, patients on 15 mg lost an average of 22.5%. Ozempic 1 mg gives 10-12%. With a limited budget or milder obesity, Ozempic is often a good start.
How much do Mounjaro and Ozempic cost per month?
Mounjaro: €176-419 depending on dose. Ozempic: €105-185. Mounjaro is 60-80% more expensive but gives around 70% more weight loss. Reimbursed for type 2 diabetes; not for off-label obesity.
Can I switch from Ozempic to Mounjaro?
Yes, under the supervision of a doctor. You usually start with the Mounjaro starting dose (2.5 mg) to limit side effects. Many patients experience extra weight loss with Mounjaro thanks to the GIP component.
Which has fewer side effects?
Side effects are comparable (nausea 15-25%, diarrhoea, constipation). Mounjaro seems to cause slightly more stomach complaints during the titration phase. With both medications, complaints usually disappear after 4-8 weeks.
Does Mounjaro also work for non-diabetics?
Yes. In the Netherlands, Mounjaro is registered for type 2 diabetes, but it is prescribed off-label for obesity (BMI ≥30 or ≥27 with comorbidity). The American variant is called Zepbound and is officially registered for obesity there.
Unsure which is the best choice?
Our BIG-registered doctors look at your medical history, BMI, blood values and goals. Based on that, they advise which GLP-1 medication gives you the best balance between effect, side effects and costs.
Want to look beyond Mounjaro and Ozempic? Read our full GLP-1 comparison in which we also include Wegovy, Saxenda and Rybelsus — the complete guide to which GLP-1 is best for you.
Looking for the next generation? Read about retatrutide — the triple agonist with 24% weight loss which is expected to enter the market from 2026/2027.