Ozempic or Mounjaro: What's the Difference?

The most important distinction is the active substance and how each medicine acts on the body.

Ozempic (semaglutide)

Ozempic contains semaglutide, a GLP-1 receptor agonist. It works by mimicking the GLP-1 hormone, which plays a role in regulating appetite and blood sugar. Many people taking it report a reduced sense of hunger and increased feelings of fullness. It is supplied as a pre-filled pen and is injected once weekly.

Mounjaro (tirzepatide)

Mounjaro contains tirzepatide, which is a dual GIP and GLP-1 receptor agonist. As well as acting on GLP-1 pathways, it also activates the GIP receptor — an additional appetite-regulating pathway. Like Ozempic, it is a once-weekly injection delivered via a pre-filled pen.

A note on Ozempic, Wegovy, and weight management

It is worth noting that semaglutide is available under more than one brand name. Wegovy is the formulation of semaglutide specifically licensed for weight management in many countries, while Ozempic is primarily licensed for type 2 diabetes. Whether a prescriber recommends one semaglutide product, the other, or Mounjaro depends on a person's individual clinical picture — not on a simple ranking of which is "best." For a broader look at how these medicines compare, see our Wegovy vs Mounjaro comparison guide and our page on Wegovy or Mounjaro: what to know.

Both medicines are subject to additional monitoring (indicated by the black triangle ▼ in their product information). Any side effects should be reported to your healthcare professional and to your national reporting scheme — for example, the UK's Yellow Card scheme or the equivalent scheme in your country.

GLP Trackr is built for people already on a GLP-1 or dual GIP/GLP-1 medicine — whether that's Ozempic, Mounjaro, Wegovy, or another prescribed medicine in this class. The app works the same regardless of which you're taking.

The feature most relevant to where you are right now is dose and injection logging: every shot you take can be recorded with the date, dose strength, and injection site, giving you a reliable history to refer back to and share with your prescriber at appointments. Alongside that, the side-effect tracker lets you log how you feel after each dose and spot patterns over time — useful context to bring to any clinical conversation. And if you want to understand your broader progress, weight and body tracking with weekly charts gives you a picture that goes beyond the number on the scale.

For a deeper look at how weight-loss results compare between these medicines in the published literature, our page on Ozempic or Mounjaro for weight loss covers what the evidence says. You can also explore what research says about Ozempic vs Mounjaro for a more detailed informational breakdown.

The choice of medicine is always your prescriber's call — not something to decide based on online comparisons. If you have questions about which medicine is appropriate for you, or whether switching might make sense, your prescriber or doctor is the right person to ask. GLP Trackr supports your journey once that decision has been made; it does not replace clinical advice.

Already prescribed and ready to track? Download GLP Trackr free on the App Store or Google Play — your first 7 days are on us, with no commitment required.