Mounjaro vs Wegovy: which is worth the difference?
Mounjaro costs €554.95 against Wegovy’s €279.95 in Ireland, almost exactly double. In head-to-head trial data tirzepatide produced a larger average weight reduction than semaglutide. Neither reaches State reimbursement when prescribed for weight loss. Which suits you depends on tolerance, budget and what your prescriber judges appropriate.
The short version
- Mounjaro costs €275 more per two-pen pack, roughly double
- Tirzepatide acts on two receptors, semaglutide on one
- Head-to-head data favours tirzepatide on average weight reduction
- Both are weekly injections; neither is reimbursed for weight loss
- Wegovy is easier to be prescribed for weight management by an Irish GP
What each one costs in Ireland
| Mounjaro | Wegovy | |
|---|---|---|
| Per pack | €554.95 | €279.95 |
| Pens per pack | 2 | 2 |
| Weeks covered | 8 | 8 |
| Difference | €275.00 more for Mounjaro | |
Over a year of maintenance that gap is substantial. Roughly six and a half packs each, so about €3,607 for Mounjaro against €1,820 for Wegovy. Nearly €1,800 a year in difference.
Both carry the same additional costs on top: €35 to €90 for a consultation, €60 to €100 for baseline bloods, and monthly reviews at the start. Full price index →
How Mounjaro and Wegovy work differently
Wegovy is semaglutide. It mimics GLP-1, a hormone the gut releases after eating, slowing gastric emptying and acting on appetite signalling in the brain.
Mounjaro is tirzepatide, and it does the same thing plus one more. It also acts on GIP, a second gut hormone. That dual action is the accepted explanation for the difference in outcomes.
Whether two receptors is meaningfully better than one for a given person is not settled at the individual level. On averages across large trials, it is.
Mounjaro vs Wegovy: what the trial data shows
The SURMOUNT programme tested tirzepatide, the STEP programme tested semaglutide at 2.4 mg, and a head-to-head comparison has since been published. Tirzepatide produced greater average weight reduction across the comparison.
Two things are worth holding onto. Averages conceal wide individual variation, and plenty of people do better on semaglutide than the average tirzepatide result. And trial participants receive structured dietary and activity support that most private patients do not.
Prescribing information for both is published by the European Medicines Agency: Mounjaro and Wegovy.
The licensing difference between Mounjaro and Wegovy
Wegovy is licensed in Ireland for weight management only. Mounjaro is licensed for both type 2 diabetes and weight management.
Practically, that means an Irish GP prescribing Wegovy for weight loss is prescribing within its licence, which is a straightforward conversation. It also means Mounjaro can reach State reimbursement if you have type 2 diabetes, where Wegovy never can. How reimbursement works →
Mounjaro and Wegovy dosing and tolerance
Both are weekly. Wegovy titrates over sixteen weeks to 2.4 mg. Mounjaro steps up in 2.5 mg increments to a possible 15 mg over twenty weeks.
Side effect profiles are similar: nausea, diarrhoea, constipation, worst in the first days after each increase. Mounjaro’s longer titration means more steps, which some people find gentler and others find drawn out.
Should you ask for Mounjaro or Wegovy?
Ask about Wegovy if cost matters, you want the simpler prescribing conversation, or you would rather start with the better-established weight management option.
Ask about Mounjaro if budget allows, you have type 2 diabetes and could reach reimbursement, or you have tried semaglutide without the result you hoped for.
Framing it as a question rather than a request tends to go better. Your prescriber is weighing your history, your other medication and your tolerance, and that is information a comparison article cannot hold.
Read next: what happens to your weight when you stop.
Mounjaro in Ireland: cost and access
Tirzepatide pricing, titration and how to be prescribed it.
GuideWegovy in Ireland: cost and access
Semaglutide licensed for weight management, and what it costs.
GuideCompare all five weight loss treatments
Cost per kilo lost, dosing and what each one is licensed for.
Let us find your price and your prescriber
Tell us your county. We will come back with the best price near you and an Irish specialist who can assess whether it suits you.
- The best price available near you, pharmacy by pharmacy
- An Irish specialist who can assess you and prescribe if suitable
- Whether your case is likely to qualify for State reimbursement
Which is easier to actually get in Ireland
Price is only half the decision if you cannot fill the prescription. Wegovy has been through Europe-wide supply constraints, and in practice availability varies pharmacy by pharmacy rather than county by county. Mounjaro has generally been more consistently available since launch.
If you are in Dublin, Cork or Galway you have enough pharmacies within reach that a few calls will usually locate stock of either. In Kerry, Donegal or Leitrim it is worth asking your pharmacy to order ahead of your repeat, particularly mid-titration when a gap means stepping back down a dose.
Mounjaro vs Wegovy: common questions
In head-to-head trial data tirzepatide produced a larger average weight reduction than semaglutide. It also costs almost exactly double in Ireland. Averages hide wide individual variation, so the larger average result is not automatically the better choice for a given person.
€275 more per two-pen pack: €554.95 against €279.95. Across a year of maintenance that is roughly €1,800.
That is a decision for your prescriber. Switching between GLP-1 treatments is done in practice, but the starting dose and titration are handled differently depending on where you are in your current schedule.
Not for weight loss. Mounjaro reaches the €80 monthly cap when prescribed for type 2 diabetes. Wegovy never does, because weight management is its only licensed indication.