Users of Mounjaro have been disappointed to learn that manufacturer’s Eli Lilly are to increase prices in the UK, this they say, is to bring UK prices closer to the higher prices currently charged in Europe and the US.
Many people choose Mounjaro because recent reports indicate that it is better for weight loss than Wegovy. But the price hike might make you want to consider changing from Monjaro injections to Wegovy.
To help you with your decision we look at the role each medicine has in a person’s weight loss journey to find out whether one really is better than the other.
When we eat our gut contains hormones called GIP and GLP-1. In a nutshell, these hormones tell the pancreas to release insulin, and the insulin moves the sugar into our cells for energy. If we eat more calories than we burn off then the body stores the extra energy, and it mostly converts to fat. Â
Once you are used to eating large portions the GIP and GLP-1 hormones don’t work so well, it is like they slow down and aren’t as efficient as they should be in telling the brain that the stomach is full. Â
Mounjaro contains tirzepatide which boosts the receptors of the GIP and GLP-1 hormones so that they begin to work efficiently again and the brain receives the message to slow your digestion down and make you feel full before you have eaten too much. Both hormones working together give the body a stronger signal than either one alone.
Wegovy contains semaglutide. It helps to activate the GLP-1 hormone which has the same effect as Mounjaro although because it only works with one hormone the signal isn’t as strong, which is why it could take longer to lose weight using Wegovy over Mountjaro.
The most common side effects are nausea and vomiting, constipation or diarrhoea, indigestion, bloating and abdominal pain. Â These are side affects that are common with both Mountjaro and Wegovy. Users of Wegovy have also reported incidents of fatigue and dizziness. Â Â
Serious side effects are also common to both medicines, apart from suicidal thoughts or depression which have been associated with Wegovy.
In May 2025 the New England Journal of Medicine published the results of a study that compared the weight loss results of participants who used either tirzepide or semaglutide for a year and a half. There were 751 participants each with an average weight of 18 stone.
Researchers found that the participants taking weekly injections of tirzepatide lost 20.2 per cent of their body weight compared to those on semaglutide who lost 13.7 per cent of their body weight.
Wegovy is less expensive than Mounjaro, although at present the price difference isn’t that great. However, when the cost of Mounjaro goes up, it may well be double the price which will make Wegovy considerably cheaper.
Both medications help you to eat less so that your body burns fat and you lose weight. The difference between Mounjaro and Wegovy appears to be that because Mounjaro uses tirzepatide which boosts GIP and GLP-1. For example,
It means that people who use Mounjaro for a year will lose more weight than someone using Wegovy over the same period. Using Wegovy might mean you have to make more effort with lifestyle changes than you would with Mounjaro.
If you have been using Mountjaro injections it is possible to swap to Wegovy. First of all you’ll need to speak to the pharmacist to make sure you’re not allergic to any ingredients in Wegovy, especially Semaglutide.
Before you begin your new dose of Wegovy you must stop taking Mounjaro and leave a gap of 7 days. It is important that you leave this gap because taking both medications at the same time will increase the risk of common side effects and more serious problems like pancreatitis.
If you are registered with our weight loss clinic then come and speak to us about making the switch. If you are thinking about using weight loss injections make an appointment to come and see us at the clinic. We’ll talk through your options and advise you on the best treatment for your lifestyle.
You can book online, give us a call on 01276 21002, or pop into the pharmacy and speak to a member of staff.
If you’re interested in losing weight by using weight management injections such us Wegovy or Mounjaro, our new service will help you. Read our latest article to find out more about weight loss medication and how we can help you.
Like all medications there can be side effects whilst using Mounjaro. One side effect that has been in the news lately is pancreatitis. To find out more about Mounjaro’s side effects read our latest blog which tells you what you can expect when you start using Mounjaro on your weight loss journey.
