Switching from Wegovy to Mounjaro

Yes, switching from Wegovy to Mounjaro is possible if you meet the criteria required to take both medications. Before you switch, your doctor will check that you meet one of the following criteria:

1. You must have a body mass index (BMI) between 27 and 30 with a weight-related health condition or
2. You must have a BMI of at least 30.

Wegovy and Mounjaro are not interchangeable medications, so you cannot just stop taking Wegovy and start taking Mounjaro. You will need to wait for 5 weeks after stopping Wegovy before you can start taking Mounjaro. This is to make sure that there is no Wegovy left in your body when starting Mounjaro, as these medications can interact and cause unwanted side effects if taken close together.

Switching from Wegovy to Mounjaro involves some simple steps.

After discussing switching from Wegovy to Mounjaro with your doctor:

1. Stop taking Wegovy when your last pen is finished. If you are experiencing side effects and do not want to finish your current Wegovy pen, you can stop straight away.
2. You should wait at least 5 weeks before starting Mounjaro to allow enough time for Wegovy to leave your system.
3. Start your first dose of Mounjaro. This will be the lowest dose of 2.5mg and then follow the usual Mounjaro dosage schedule.

Even if you were on the highest maintenance dose of Wegovy before you switched, you will always need to start on the lowest Mounjaro dose. That’s because they are different medications, and to reduce the risk of side effects it’s best to start on the lowest dose and gradually increase your dose up to the maintenance dose or the dose you tolerate best.

There are a few reasons why some people choose to switch from Wegovy to Mounjaro, including:

Effectiveness

Clinical trials show that Mounjaro is associated with greater weight loss. At the highest maintenance dose of 15mg per week, Mounjaro helps people lose an average 22.5% of their initial body weight. At the highest Wegovy dose of 2.4mg per week, people can lose an average of 15% of their starting weight after 68 weeks.

Side effects

Both weight loss injections can cause side effects but if you’re experiencing adverse effects on Wegovy, you may want to switch to Mounjaro. However, there is no guarantee that you will not experience Mounjaro side effects if you switch because everybody reacts differently to medications.

Results

If you are not experiencing the weight loss you’d hoped for while using Wegovy, you may want to switch to Mounjaro. If you have not lost at least 5% of your starting weight within 6 months of starting Wegovy, your doctor may suggest that you stop using it.

Anyone who meets the criteria for both weight loss medications can make the switch from Wegovy to Mounjaro.

If you are already taking Wegovy, you will likely be able to use Mounjaro. Your doctor will check that you meet the following eligibility criteria before helping you to swap medications:

• a BMI between 27 and 30 with a weight-related condition such as high blood pressure, prediabetes, or obstructive sleep apnoea or a BMI of 30 or more
• not breast feeding or pregnant
• have no pre-existing medical conditions that mean Mounjaro is unsuitable for you, such as an allergy to the active ingredient, tirzepatide
• over 18 years old
• not taking any medications which may interact with Mounjaro

Switching from Wegovy (semaglutide) to Mounjaro (tirzepatide) for weight loss requires careful consideration. No matter what dose you are currently on for Wegovy, you will always need to start Mounjaro at the lowest dose 5 weeks after your last Wegovy dose.

Here is a Wegovy to Mounjaro conversion chart to help you better understand the equivalent doses:

For more information on Mounjaro Dosages for Weight Loss, take a look at our guide.

When you switch from Wegovy to Mounjaro, you may notice some changes in your appetite as Wegovy leaves your system. For example, you may notice that your appetite increases in the short term because semaglutide will no longer bind to the receptors in your brain that signal that you feel full.

However, this will be a temporary effect because Mounjaro works in the same way as Wegovy by binding to the glucagon-like peptide-1 (GLP-1) receptors, so you should notice positive changes to your appetite as your Mounjaro dose increases.

When you switch, it is unlikely that you will experience Wegovy withdrawal symptoms but you may notice appetite changes, body changes, or stomach upset. Rather than withdrawal symptoms, these are signs your body is returning to its baseline.

As your dose of Mounjaro titrates up and your body gets used to the medication, you are more likely to notice better weight loss results.

The simple answer is yes – if you are suitable for Mounjaro treatment, you should consider switching from Wegovy to Mounjaro. That’s because Mounjaro is often a better weight loss option and is associated with greater weight loss.

If you are interested in making the change from Wegovy to Mounjaro, you can begin a consultation with one of our doctors to see if Mounjaro is suitable for you:

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