Written and medically reviewed by W. van Donselaar, MD, BIG 79020681301, on 26-05-2026.
Ozempic and Mounjaro are similar. They are both injections that you put once a week, they both reduce your appetite, and they are both mentioned in news stories about losing weight. But they are not the same. The active ingredients differ, the mechanism of action is broader with Mounjaro, and the weight loss measured in studies also differs.
Which remedy is better suited to you, we cannot say in advance. During the intake, our doctors look at your BMI, your medical history and additional conditions. Then, together with you, we determine which remedy is available and appropriate.
What are Ozempic and Mounjaro?
Ozempic
Contains the active substance semaglutide. This is a GLP-1 receptor agonist, a medicine that mimics the body's own intestinal hormone. That hormone, GLP-1, is released after a meal and makes you feel satiated faster and keeps your blood sugar stable. Ozempic is registered in Europe for type 2 diabetes, with a maximum dose of 2 mg per week.
Mounjaro
Contains a different active substance, namely tirzepatide. This is not a pure GLP-1 receptor agonist. Tirzepatide acts on GLP-1 as well as on a second gut hormone, GIP. Therefore, the mechanism of action is broader. Mounjaro is registered for type 2 diabetes and weight treatment, with a maximum dose of 15 mg per week.
You get both drugs in a pre-filled pen that you inject yourself under the skin, once a week on a set day.
A separate registration exists for pure weight treatment with semaglutide, namely Wegovy, with a higher maximum dose than Ozempic.
How do they differ in operation?
The main difference is in which hormones the drugs mimic. Semaglutide works only on GLP-1. Tirzepatide acts on GLP-1 as well as on GIP, and therefore has a broader effect. The table below shows how the two relate to each other.
| Feature | Ozempic (semaglutide) | Mounjaro (tirzepatide) |
|---|---|---|
| Works on | GLP-1 | GLP-1 and GIP |
| Effect on hunger and satiety | you feel full faster, your stomach empties slower, and you feel less hungry between meals | same, but via BIP often stronger |
| Effect on blood sugar | stabilises blood sugar, triggers insulin only when blood sugar is elevated | same, plus impact on insulin sensitivity and lipid metabolism |
| Maximum dose per week | 2 mg | 15 mg |
| Registered in the Netherlands for | type 2 diabetes | type 2 diabetes and weight management |
Side effects: how do they compare?
Both drugs have largely the same side effects. Gastrointestinal complaints are the most common.
- nausea
- diarrhoea
- vomit
A few side effects are less common but relevant with both drugs.
- gallstones
- pancreatitis
- increased hypo-risk in type 2 diabetes (in combination with insulin or sulphonylurea derivatives)
If you want the full picture by means, look at the side effects of Ozempic and the side effects of Mounjaro.
What does the research say about weight loss?
| Research | Medium | Dose per week | Duration | Average weight loss | placebo |
|---|---|---|---|---|---|
| STEP-1 (2021) | semaglutide | 2.4 mg | 68 weeks | 12 to 15% | 2 to 3% |
| SURMOUNT-1 (2022) | tirzepatide | 15 mg (highest dose) | 72 weeks | 20%, at lower doses 15 to 18% | 3% |
The 2.4 mg from STEP-1 is the Wegovy dose, higher than the Ozempic maximum dose of 2 mg. In both studies, participants also received intensive lifestyle counselling.
There are two things to keep in mind with these figures.
They are averages, not promises. Individual variation is great. Some participants lost less, others more, and for some, both drugs worked insufficiently. What you yourself achieve depends on your starting values, your dosage, your lifestyle and how your body reacts.
The trials are difficult to compare directly. Study design, participants and duration differ between STEP and SURMOUNT. The SURMOUNT-5 trial from 2024 did compare both drugs within one study, and in it tirzepatide was on average more effective. Even then, the individual response rate remains decisive.
Which one do you choose?
The choice depends on a number of medical factors that a doctor assesses.
Your indication
For type 2 diabetes, both drugs are registered. For pure weight treatment without diabetes, the situation is different. Mounjaro is registered for that in the Netherlands, while semaglutide for obesity falls under Wegovy and not Ozempic. The choice then goes mainly between Wegovy and Mounjaro.
Your medical history
Some conditions exclude both agents, such as a personal or family history of medullary thyroid carcinoma. Gastrointestinal problems, previous pancreatitis or kidney problems may weigh in. In women with an active desire to have children, GLP-1 medications are avoided because there is insufficient certainty of safety during pregnancy.
Availability and remuneration
Tirzepatide entered the Dutch market later than semaglutide and has been poorly available at times in recent years. Reimbursement through health insurance varies by drug and indication. For pure obesity treatment, both drugs are usually not reimbursed.
We assess during the intake Whether a pathway is possible, and if so, by what means. Want a first impression of whether you qualify, do the check.
Unsure which remedy is right for you? Discuss it with a doctor. Schedule a no-obligation online intake and find out what is possible for you.
What a course at Weightconsult can do for you
At Weightconsult, we supervise trajectories with Ozempic injections and Mounjaro injections completely online. Here's how it works.
- You do a digital intake, in which you share your situation and health with us.
- Weightconsult's own doctor will assess whether a course is possible, and if so, with which drug.
- After a valid prescription, Pharmacy eFarma takes care of delivery to your home.
- During the course, you will receive guidance around your build-up schedule, your diet and dealing with any side effects.
Which remedy best suits you, we determine together with you during the intake, in which we look at your whole situation and explain which options are and are not open.
Key points blog at a glance
Is Mounjaro more effective than Ozempic?
Is Mounjaro more effective than Ozempic?
In clinical trials, tirzepatide showed greater weight loss on average than semaglutide, especially at the higher doses. The 2024 SURMOUNT-5 trial confirmed this in a direct comparison. Individual variation is just large, and what is an average in studies does not automatically apply to you.
Can I choose between Ozempic and Mounjaro by myself?
Can I choose between Ozempic and Mounjaro by myself?
No. Both drugs are prescription drugs, so the choice is made by a doctor. Who looks at your indication, your medical history and availability. During the intake, we discuss which options are available to you.
What are the costs?
What are the costs?
The price varies per drug, per strength and per pharmacy. Whether your health insurance will co-pay depends on the indication and your policy. For pure weight treatment, both drugs are usually not reimbursed. Check the current price and your own reimbursement with your pharmacy and health insurer.
Can I switch from Ozempic to Mounjaro?
Can I switch from Ozempic to Mounjaro?
A switch is possible, but is always done under medical supervision. This will require a new fitness assessment and build-up schedule, along with an evaluation of why you want to switch.
How long have you been using these drugs?
How long have you been using these drugs?
There is no fixed term for it. For weight treatment, it is usually a longer treatment because weight often comes back after stopping. How long you continue, you evaluate with your doctor based on your results and how you feel.