Wegovy® and Mounjaro® are both once-weekly injectable treatments used for weight management. However, they contain different active ingredients.
- Wegovy® contains semaglutide.
- Mounjaro® contains tirzepatide.
Both treatments work alongside changes to diet and physical activity to support weight loss. The amount of weight lost varies between individuals, so results experienced by one person should not be used to predict how another person will respond.
How effective are Wegovy® and Mounjaro®?
Clinical studies have shown that both treatments can lead to significant weight loss when used alongside appropriate lifestyle changes.
Wegovy® has been shown to achieve around 20.7% average body weight loss in some patients, while Mounjaro® has demonstrated weight loss of around 20%.
Individual results will vary depending on factors including treatment response, dose, diet, physical activity and adherence to treatment.
What are the doses?
Wegovy® and Mounjaro® have different dosing schedules.
Treatment usually begins at a lower dose before gradually increasing. This allows your body to adjust to the medication and can help reduce the likelihood of side effects.
Wegovy®:
0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg → 7.2mg
Mounjaro®:
2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
Always follow the dosing instructions provided by your prescriber. You should not increase, decrease or otherwise change your dose without appropriate clinical guidance.
Incorrect use of prescription medication can cause harm and may also delay the processing of your order.
Cardiovascular considerations
Wegovy® has been shown to reduce the relative risk of certain major cardiovascular events, including non-fatal heart attack, non-fatal stroke and cardiovascular death, in certain adults with established cardiovascular disease.
The suitability of either treatment will depend on your individual circumstances and medical history. Our clinical team will assess whether a treatment is appropriate for you.
Oral contraception
There is an important difference to consider if you take an oral contraceptive.
Wegovy® has not been shown to reduce the effectiveness of oral contraception.
Mounjaro®, however, can reduce the effectiveness of oral hormonal contraceptives after starting treatment and following dose increases.
If you use an oral contraceptive while taking Mounjaro®, you may be advised to use an additional barrier method, such as condoms, or switch to a non-oral method of contraception for 4 weeks after starting Mounjaro® and for 4 weeks after each increase in dose.
Using the pens
There is also a small difference in how the injection pens are prepared.
Wegovy® only needs to be primed before the first injection with each new pen.
Mounjaro® requires the pen to be primed before each injection.
Always follow the instructions supplied with your medication and the guidance provided by your healthcare professional.
Are the side effects different?
Wegovy® and Mounjaro® can cause similar gastrointestinal side effects, including nausea, vomiting, diarrhoea, constipation and abdominal discomfort.
However, the side-effect profiles are not identical because the treatments contain different active ingredients.
For detailed information about possible side effects, warnings and how to manage them, please see our dedicated Wegovy® and Mounjaro® side-effect guidance.