Is there a daily injection for weight loss?

Simon Edward • 26 November 2024

Weekly obesity injections are well-known. But is there a daily injection for weight loss? Find out in our guide.

Weekly obesity injections are well-known. But is there a daily injection for weight loss? Find out in our guide.

If you're exploring options for losing weight or have been following the news, you've probably heard of the injectable medications Wegovy and Mounjaro.


These game-changing obesity treatments are approved for use in the UK with a prescription. For many patients, they've proven to be viable alternatives to gastric surgery.


If you take Wegovy or Mounjaro, you can expect to lose more weight than you would with diet and exercise alone. In a clinical trial, Wegovy patients lost an average of 15% of their body weight.¹ In the Mounjaro trial, the average weight loss was 21%.²


However, the injections are not magic wands. You'll still need to follow a sensible diet and active lifestyle to achieve the results you want. And, like all drugs, they come with a list of potential side effects.


Still, the benefits are clear. Unlike with bariatric surgery, which is often irreversible, treatment can be stopped at any time. What's more, you only have to take the injections once a week for the treatments to work.


But these once-weekly injections aren't the only options available. There's also a daily weight loss injection called 'Saxenda', which was launched in the UK back in 2017.


How does Saxenda compare to Wegovy and Mounjaro?


Saxenda, Wegovy and Mounjaro are all part of a family of drugs called 'incretic mimetics'. They work by mimicking natural incretin hormones. Your body uses these hormones to control hunger and regulate blood sugar, among other things.


This means the effects of each drug are largely similar. They help you feel full and limit food cravings, so you're better equipped to take control of your eating habits.


The potential side effects of each drug are also similar, with the most commonly reported side effects for all three including nausea, vomiting and diarrhoea.

A woman is laying on a bed with her hands on her stomach.

However, side effects tend to be more pronounced with Saxenda than Wegovy – and Wegovy tends to produce slightly worse side effects than Mounjaro.


That's the similarities. Now, let's look at what's different between the three medications.


One of the most obvious differences relates to dosing schedules. While Wegovy and Mounjaro only need to be taken once per week, Saxenda must be injected daily.


This is because Wegovy and Mounjaro stick around in your body for longer than Saxenda. Wegovy and Mounjaro have a half-life of seven days: after one week, half of the medication will still be in your system. Saxenda's half-life, however, is just 24 hours.


However, it takes longer to reach the highest (maintenance) dose with Wegovy and Mounjaro.


With Wegovy, it takes 5 months to reach the maintenance dose.

With Mounjaro, it takes 6 months.

With Saxenda, it takes 4 weeks.


Finally, Saxenda is usually less effective for weight loss than the other two medications.


We know this because a 2022 clinical trial directly compared the active ingredients in Saxenda (liraglutide) and Wegovy (semaglutide).


In that trial, Saxenda users lost 6.4% of their body weight over 68 weeks. Wegovy users, however, lost 15.8%.³


And as we've seen, other clinical trials have demonstrated a 15% average weight loss with Wegovy¹ and a 21% average for Mounjaro.²


This is one reason why we only offer Mounjaro and Wegovy as treatment options at SemaPen. It's very important to us that we offer our patients the most effective and best-tolerated medications available.


SemaPen's sensible and effective weight loss plans are designed by obesity doctors in the UK. If you've tried to lose weight without success, why not learn more about our Wegovy and Mounjaro treatment programmes?


Sources


1. Wilding, J.P.H. et al. (2021) "Once-weekly semaglutide in adults with overweight or obesity" New England Journal of Medicine, 384(11) https://doi.org/10.1056/NEJMoa2032183

2. Jastreboff, A.M. et al. (2022) "Tirzepatide Once Weekly for the Treatment of Obesity" New England Journal of Medicine, 387(3) https://doi.org/10.1056/NEJMoa2206038

3. Rubino, D.M. et al. (2022) "Effect of Weekly Subcutaneous Semaglutide vs Daily Liraglutide on Body Weight in Adults With Overweight or Obesity Without Diabetes: The STEP 8 Randomized Clinical Trial" JAMA, 327(2) https://doi.org/10.1001/jama.2021.23619

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