Wegovy and Mounjaro are both used to aid people in their weight loss journeys, and they have a lot in common. They’re both GLP-1 receptor agonists, and they work in similar ways, but people often want to know if anything sets them apart from each other.
They aren’t identical, and some people might find that they prefer using one or the other. So, here we’ll compare Wegovy vs Mounjaro to find out which is better for weight loss in 2026.
How do Wegovy and Mounjaro work?
Both Wegovy and Mounjaro are GLP-1 receptor agonists, meaning they mimic GLP-1, a hormone. GLP-1 is produced by the gut and helps the body regulate appetite, slow the emptying of the stomach, and reduce food noise.
As a result, people taking GLP-1 medications like Wegovy and Mounjaro tend to eat less food and consume fewer calories, helping support gradual weight management.
In the UK, both medications are approved for weight management by the Medicines and Healthcare products Regulatory Agency (MHRA), and both are self-administered weekly via injection.
The differences between Wegovy and Mounjaro
Although they work in similar ways, Wegovy and Mounjaro contain different active ingredients. Wegovy contains semaglutide, while Mounjaro contains tirzepatide.
Tirzepatide is actually known as a dual agonist, because it mimics both GLP-1 and GIP, another hormone. It can help the body burn more energy when used alongside GLP-1. Because of this, some people see greater weight loss on Mounjaro at higher doses.
One area where Wegovy might differ from Mounjaro, however, is that it’s thought to have cardiovascular benefits. In fact, it’s approved to reduce the risk of serious cardiovascular problems in obese or overweight adults.
What does the latest research say?
Both Wegovy and Mounjaro are effective in helping people lose weight, but there is evidence that Mounjaro could be more effective at higher doses, likely because it’s a dual agonist.
One results comparison study released last year indicated that people taking semaglutide lost 13.7% of their body weight, compared to the 20.2% that people taking tirzepatide lost.
Meanwhile, people on tirzepatide saw their waists shrink by an average of over 5cm more than those taking semaglutide.
More tirzepatide vs semaglutide analysis, this time from 2026, found that tirzepatide and semaglutide are both effective in helping with weight loss, but found that tirzepatide may rank slightly higher than semaglutide in average weight loss outcomes.
One more study from 2024 found that tirzepatide usage saw people lose almost 7% more body weight on average after a year than semaglutide usage.
Despite these findings, however, the participants in this prior research who used semaglutide would have taken a maximum dose of 2.4mg, whereas the maximum dose of Wegovy increased to 7.2mg at the start of 2026. On this new, higher dose, people may notice greater weight loss. However, more research will need to be conducted.
Side effects of Wegovy vs Mounjaro
While weight loss will be the most important factor for many people when they’re deciding between Wegovy and Mounjaro, side effects are something a lot of people consider.
Fortunately, most side effects of both GLP-1 medications – like nausea, vomiting, diarrhoea and constipation – tend to be fairly mild, with symptoms getting better over time. And there’s not a lot of difference between the two. According to the 2025 study, just under four out of five people taking either medication reported at least one side effect, between 77% and 79%.
About 6% of those taking tirzepatide and 8% of those taking semaglutide stopped treatment before the end of the study due to the side effects, which suggests that side effects can be manageable for the vast majority of people.
If side effects are a concern, or you’d like to find out more about whether Wegovy or Mounjaro might be best to help you lose weight, it’s a good idea to speak to your doctor or a prescriber. They’ll be able to help you figure out which medication could be best for you to try.
Frequently asked questions
Is Wegovy or Mounjaro more effective for weight loss?
Both Wegovy and Mounjaro are effective in helping people lose weight. There is evidence that Mounjaro might lead to greater weight loss on average at higher doses, but results can vary from person to person depending on factors like lifestyle and how the body responds to treatment.
What’s the difference between tirzepatide and semaglutide?
Tirzepatide and semaglutide are very similar, but tirzepatide is a dual receptor agonist, mimicking both GLP-1 and GIP, whereas semaglutide only mimics GLP-1. Tirzepatide’s dual function may be why Mounjaro is more effective for weight loss on average.
Are Wegovy and Mounjaro meant to be used long term?
Because obesity is now considered a chronic condition, Wegovy and Mounjaro are designed for long-term weight management. They shouldn’t be considered a short-term fix but part of a healthy lifestyle.