Can I switch from Mounjaro to Wegovy?

Yes, you can switch from Mounjaro to Wegovy with the support of a medical professional. If you’re currently taking Mounjaro and considering changing to Wegovy, you’re not alone. A rise in prices of some weight loss treatments means many people are considering which weight loss medication is most effective and affordable. As you consider these changes it’s important you know what to expect, and how dose adjustments work when moving between these two medications.

What are Mounjaro and Wegovy?

Mounjaro and Wegovy are different types of weight loss medications, taken as weekly injections. They belong to a group of medications called glucagon-like peptide 1 (GLP-1) receptor agonists. They both work by mimicking GLP-1, a naturally occurring hormone that manages hunger levels.

While Mounjaro and Wegovy weight loss injections work in broadly the same way, they have different active ingredients. The active ingredient in Mounjaro is tirzepatide, while the active ingredient in Wegovy is semaglutide.

Wegovy was the first GLP-1 weight loss injection approved to treat obesity and to support obesity-related health conditions, such as diabetes, in the UK. It’s also worth noting Wegovy is currently the only GLP-1 medication licensed in the UK to reduce the risk of major cardiac events, such as a heart attack or stroke, in people with obesity and established heart disease.

Both Mounjaro and Wegovy are only available on prescription via regulated online services or selected NHS weight loss clinics.

Can I switch from Mounjaro To Wegovy?

Yes, this is possible under medical supervision. While both medicines help with weight loss and blood sugar control, they work slightly differently and have different dosing schedules.

You cannot alternate between the two medications or inject both medications at the same time. However, you can make a permanent switch from one to the other.

While dosing works differently, as long as you take a week long break you can follow up your next dose of the different medication on your usual dosing schedule.

It’s important to note that your doses are not interchangeable and a member of our clinical team will assist you with understanding which strength would be most suitable for you.

What’s the difference between Mounjaro and Wegovy?

While both are injectable GLP-1-based medications, there are key differences:

The main distinction is that Mounjaro targets two receptors (GIP and GLP-1), while Wegovy targets only GLP-1. This can influence both effectiveness and side effects.

Read more about your weight loss options on our Weight Loss page.

Is Wegovy as good as Mounjaro?

Clinical trials suggest Mounjaro may produce greater average weight loss than Wegovy for many patients, likely due to its dual-receptor mechanism.

Over a 72 week clinical trial on Mounjaro the average weight loss was up to 22.5% of body weight, while a 72 week trial of Wegovy saw up to 17.5% body weight loss on Wegovy 2.4mg and up to 20.7% body weight loss on Wegovy 7.2mg (which is due to be released late 2025).

From September 2025, it is likely that Wegovy will be available privately to UK patients at around half the price (or less) than the equivalent maintenance dose of Mounjaro so the price paid for the weight loss achieved may be more favourable to Wegovy if affordability of treatment is an influence.

It’s worth remembering that individual results vary and different people react differently to each medication. Wegovy also has a longer track record for weight management. The amount of weight you can lose will be influenced by any lifestyle changes you make too.

Both treatments appear to have similar levels of gastrointestinal side effects in clinical trials.

How Do I Know Which Strength Of Wegovy To Choose When Switching From Mounjaro?

You can’t make a direct “mg-for-mg” switch between Mounjaro and Wegovy because they are different drugs with different strengths. Instead, our medical professionals use a dose conversion approach to decide an appropriate switching strength.

As part of the process our clinical team will need to assess your current Mounjaro dose and tolerance, and then convert this to an appropriate strength from Wegovy, which is based on a number of factors.

It may not always be possible to just start on the same equivalent strength and you may need a step down. This will be followed by gradual titration increase every 4 weeks until reaching a maintenance dose that's suitable for you.

The slower start helps reduce gastrointestinal side effects and gives your body time to adjust to the new medication. Nevertheless, it’s important that you monitor your side effects and, if necessary, slow titration.

An example of dose switching between Mounjaro and Wegovy is detailed in the table below.

Please note, depending on your medical history, previous weight loss, incidence of side effects, and other relevant details, our clinicians may suggest a different strength which is more appropriate for you.

Will Switching Halt My Weight Loss?

Potentially, yes. Some people see a brief pause in weight loss after switching, which is usually temporary. For many however switching can assist you moving forward. You may be at a point where your weight loss has plateaued, or you have struggled with side effects.

You may find that your new weight loss medication suits you better, and this will allow you to increase your doses smoothly, which could provide better results over time.

Keeping your habits consistent and having patience is also important. Your weight loss journey is as unique as you, but if you are considering switching, complete an online consultation and a member of our clinical team can provide the help and support you need to take charge of your weight loss journey.