Jump to: 1. Tirzepatide | 2. Semaglutide | 3. Liraglutide | What weight-loss medications will be available in the future? | Weight-loss injections aren’t a magic pill
Based on data from randomised controlled trials (the gold standard of medical research), the best weight-loss injection available in the UK in 2025 is called tirzepatide, sold under the brand name Mounjaro in the UK.
Research has shown that Mounjaro supports an average weight loss of around 25% after one year.
Other options available in the UK are semaglutide and liraglutide. Below, we’ve ranked the top three weight-loss injections available in the UK in 2025.
- Tirzepatide (Mounjaro): Average weight loss of 25%
- Semaglutide (Wegovy): Average weight loss of 15-17%
- Liraglutide (Saxenda): Average weight loss of 5-7%
1) Tirzepatide (Mounjaro)
The best weight-loss injection available in the UK in 2025 is tirzepatide, sold under the brand name Mounjaro.
Tirzepatide has been approved in the UK for weight loss and type 2 diabetes. It’s currently available to purchase privately for weight loss, assuming you meet the eligibility criteria.
Research has shown that tirzepatide supports an average weight loss of around 25% after one year. This study also showed this weight loss was maintained after 20 months on the medication.
Tirzepatide is a weight-loss injection administered weekly and manufactured by the pharmaceutical company Eli Lilly.
2) Semaglutide (Wegovy and Ozempic)
The second-best weight-loss injection available in the UK in 2025 is semaglutide 2.4 mg (Wegovy).
Research has shown that semaglutide 2.4 mg (Wegovy) can support weight loss of around 16% after one year.
Wegovy has the same active ingredient as the type 2 diabetes medication Ozempic. Ozempic is available in doses up to 1 mg but is no longer available for weight loss in the UK.
Semaglutide is a weight-loss injection that you administer once weekly. It’s manufactured by the pharmaceutical company Novo Nordisk.
3) Liraglutide (Saxenda)
Liraglutide is the third-best weight-loss injection available in the UK in 2025 (Saxenda). Research shows that liraglutide supports average weight loss of 5-7% after one year.
Saxenda is also prescribed for people living with type 2 diabetes, and while its impact on weight loss is modest, Saxenda has a very positive impact on blood sugar control.
One study showed that Saxenda supported over 56% of participants in lowering their blood sugars below the diagnostic threshold for type 2 diabetes.
What weight-loss medications will be available in the future?
Several promising medications are currently in development that may expand treatment options for individuals seeking medical support for weight loss.
Retatrutide (no brand name, Eli Lilly)
Retatrutide represents an innovative approach to weight loss through its unique triple action.
This medication works by simultaneously targeting three hormones:
- GLP-1: Reduces food-seeking behaviours and appetite while supporting blood sugar regulation
- GIP: Enhances blood sugar control and energy storage management
- Glucagon: Maintains blood sugar balance and supports metabolism during fasting and exercise
Recent randomised controlled trials have shown striking results, with 100% of participants achieving at least 5% weight loss and an average weight loss of 24%.
Oral semaglutide 50mg (Rybelsus, Novo Nordisk)
A significant advancement in weight-loss medication is the development of a higher-dose oral (tablet) form of semaglutide.
Recent phase 3 trial results have demonstrated impressive outcomes:
- Average weight loss of 15.1% after 68 weeks
- 85% of participants achieved at least 5% weight loss
- 69% achieved at least 10% weight loss
- 54% reached at least 15% weight loss
- 34% accomplished 20% (or greater) weight loss
Weight-loss injections aren’t a magic pill
Weight-loss injections are most effective when combined with a healthier lifestyle. They can help kickstart weight loss while you commit to developing healthier habits.
Mounjaro and other weight loss injections, like Ozempic and Wegovy, can allow you to make lifestyle changes to support long-term weight loss.
These medications can help silence food-related thoughts and give you a boost of confidence with more immediate weight-loss results.
Second Nature’s medication-supported programmes
Second Nature has two medication-supported programmes: a Wegovy weight-loss programme and our Mounjaro weight-loss programme.
For peace of mind.
Second Nature has worked with the NHS for over 6 years providing weight-loss programmes across the UK.
Whilst our Wegovy and Mounjaro weight-loss programmes are private and not currently used by the NHS, we’ve built the programmes with a focus on scientific evidence, patient safety, and data security.
We hope that our 6+ years of working with the NHS and building a track record of effective weight-loss results will give you peace of mind to give us a try.
