Switching between Mounjaro and Wegovy: how it works

Glucagon-like peptide-1 (GLP-1) receptor agonists are a type of medication recently approved for the treatment of weight loss.¹ Though initially licensed for reducing blood sugar in individuals with type-2 diabetes, they also have the added benefits of slowing gastric emptying, reducing appetite, and aiding in weight loss, all of which contribute to better metabolic health.¹

However, not all GLP-1 receptor agonists are the same. While they share common features, there are differences in how they're administered and their specific actions in the body. For example, some are injected daily, while others are weekly.¹ Additionally, certain medications like Wegovy have shown cardiovascular benefits, which might make them a preferred choice for individuals with a higher risk of heart disease.²

In this blog, we'll explore the considerations and practicalities of switching between two popular GLP-1 receptor agonists: Mounjaro and Wegovy. Whether you're considering a change due to side effects, effectiveness, or lifestyle compatibility, understanding these options can help you make an informed decision in consultation with our clinicians or your local GP.

Why change?

There are many reasons why you might want to switch from Wegovy to Mounjaro. For starters, though both of these belong to the same class of medications, they work slightly differently, meaning that some people may see a better response in one over the other. Wegovy is a GLP-1 receptor agonist, whereas Mounjaro works on both GLP-1 and GIP receptors, which may benefit some individuals more.^3,4 Though this is reflected in studies, real-life applications of these medicines may differ.

Likewise, cardioprotective benefits are also significant, particularly for those at higher risk of heart disease. Wegovy, for instance, has shown cardiovascular benefits that might make it a preferred choice for such patients.²

And, one of the most common reasons why people want to switch – the side effects.¹ The side effect profiles for these medicines are similar, but that doesn’t mean you’ll react the same to both. For example, just because they can both cause gastrointestinal side effects like nausea, vomiting, and stomach pain, doesn’t mean you’ll experience these side effects with both medicines. Ultimately, it’s about finding what works best for you.

Can anyone switch?

The criteria for starting both Wegovy and Mounjaro are similar. You shouldn’t have any underlying medical conditions or be taking any medicines that can interfere with how the medicine works. Your eligibility will be determined during an initial consultation with one of the Numan physicians.

Mounjaro vs. Wegovy comparison

Here's a quick comparison to help you understand the differences and similarities between these two medications:

Mounjaro vs. Wegovy comparison

Here's a quick comparison to help you understand the differences and similarities between these two medications:

Switching between Wegovy and Mounjaro

Making the transition from Wegovy to Mounjaro requires careful planning and management under the guidance of a clinician.¹ There’s a process which your doctor has to follow when making this switch. For example, switching from Wegovy to Manjaro Involves the following steps:

1. Take your final dose of Wegovy. Your clinician will tell you when this should be, but the dose is often taken at the same time and day you usually take it.

2. Take your first dose of Mounjaro. This will often be 2.5mg, which is the starting dose. However, if your Wegovy dose was 2.4mg, you may be initiated on a higher, 5mg dose of Mounjaro.

3. Your dose will then be titrated based on your response to the medication.

The same steps above apply if switching from Mounjaro to Wegovy, with the doses reversed depending on which medication you’re switching from. Remember, this decision isn’t one that should be taken lightly. We urge you to communicate all of your queries, concerns, and general questions with your healthcare provider so that any medication switch is carried out in line with your health and best interests.

Some things shouldn’t change

If you’re deciding on switching weight loss medications, it’s important not to change the healthy lifestyle behaviours you’ve adopted alongside your existing medication. Weight loss medicines are not a replacement for moving more and eating a balanced diet. Instead, they’re a catalyst that enables you to benefit from your new lifestyle earlier, with hopes of committing you to a lifetime of healthy change.

The ultimate goal is to make the maintenance of weight, or weight loss in the future, feel habitual and easier to implement. If you’re finding it difficult to shift your mindset to one that aligns with your goals, it may be worthwhile to get in contact with one of the Numan health coaches. They’re there to help you develop a new relationship with food and movement that removes elements of guilt associated with the things that give you joy, while encouraging you to actively find healthy living habits that meet your expectations.

The numan take

Switching between weight loss medications requires careful consideration and guidance from your healthcare team. Before making a decision, think about why you want to switch and the safest way to do so. Always consult your healthcare provider to ensure it's the right move for you.

References

1. Jain, A. B., Ali, A., Gorgojo Martínez, J. J., Hramiak, I., Kavia, K., Madsbad, S., … Vilsbøll, T. (2021). Switching between GLP‐1 receptor agonists in clinical practice: Expert consensus and practical guidance. International Journal of Clinical Practice, 75(2). doi:10.1111/ijcp.13731

2. Lincoff, A. M., Brown-Frandsen, K., Colhoun, H. M., Deanfield, J., Emerson, S. S., Esbjerg, S., … Ryan, D. H. (2023). Semaglutide and cardiovascular outcomes in obesity without diabetes. The New England Journal of Medicine, 389(24), 2221–2232. doi:10.1056/nejmoa2307563

3. Wilding, J. P. H., Batterham, R. L., Calanna, S., Davies, M., Van Gaal, L. F., Lingvay, I., … Kushner, R. F. (2021). Once-weekly semaglutide in adults with overweight or obesity. The New England Journal of Medicine, 384(11), 989–1002. doi:10.1056/nejmoa2032183

4. Aronne, L. J., Sattar, N., Horn, D. B., Bays, H. E., Wharton, S., Lin, W.-Y., … SURMOUNT-4 Investigators. (2024). Continued treatment with tirzepatide for maintenance of weight reduction in adults with obesity: The SURMOUNT-4 randomized clinical trial. JAMA: The Journal of the American Medical Association, 331(1), 38. doi:10.1001/jama.2023.24945