Mounjaro vs Wegovy: Which Weight Loss Solution Is Right for You?

Mounjaro vs Wegovy: Compare the UK’s Leading Weight Loss Injections

Trying to choose between Wegovy and Mounjaro? The two treatments are revolutionising the way that people lose weight but they work in different ways, can cause different side effects and are suitable for different needs. In this handy how-to guide, we break down what sets each injection apart, how much weight you could lose, how much it will cost and which might suit your lifestyle best. Let us find the one that is right for you.

This guide is filled with expert advice, patient testimonials and UK-based knowledge to help you take that next step towards a healthier you.

 

What is Mounjaro?

Mounjaro (tirzepatide) was originally developed for type 2 diabetes and comes as an injection that patients take once a week. It now also has UK approval for effective weight loss treatment. Mounjaro does that by mimicking two gut hormones. the GLP-1 and GIP, that make you feel full and regulate blood sugar levels.

 

What is Wegovy?

Wegovy (semaglutide) is a higher dose formulation of Ozempic, which is manufactured by Novo Nordisk. It is authorized for weight loss in adults with obesity, as well as in those who are overweight and have weight related medical condition. It does this by mimicking the GLP-1 hormone, which decreases hunger and slows the rate your stomach empties. See NICE’s announcement here.

 

How Mounjaro Works (tirzepatide and dual agonist action)

What sets Mounjaro apart is that it attacks two hormone receptors, GLP-1 and GIP. GLP-1 inhibits appetite as well as insulin, GIP enhances the effects of GLP-1 and may decrease nausea. This “dual agonist” strategy could make Mounjaro more effective for some people.

 

How Wegovy Works (semaglutide and GLP-1 action)

Wegovy goes after only one hormone: GLP-1. This helps you feel full sooner and slower digestion keeps you full longer so you eat less. It works and has been studied thoroughly, but it does not offer the extra GIP benefits that Mounjaro does.

 

Efficacy Comparison

Mounjaro:

• Average Weight Loss: 20%–22.5% body weight.
• Treatment Duration: 72–88 weeks.
• Clinical Trial: SURMOUNT-1.

Wegovy:

• Average Weight Loss: 14.9%–15.8% body weight.
• Treatment Duration: 68 weeks.
• Clinical Trial: STEP-1.

 

How Much Weight Can You Lose?

• Mounjaro: Up to 25% of your body weight with lifestyle modifications
• Wegovy: An average of 15–17% with starting body weight.

 

Clinical Studies and Real-World Data

In a study, those with obesity who did not have diabetes lost more weight and had a larger reduction in waist size after 72 weeks of taking the active ingredient tirzepatide than did those treated with semaglutide.

 

Mounjaro vs Wegovy Side Effects

Both can bring digestive side effects, particularly when you first start them or raise the dose:

• Nausea
• Vomiting
• Diarrhoea
• Constipation
• Bloating

These are typical and tend to resolve over a couple of weeks.

 

Common vs Severe Side Effects

Common:

• Feeling tired
• Headache
• Heartburn
• Loss of appetite

Less common but more serious:

• Pancreatitis (inflammation of the pancreas)
• Gallbladder issues
• Serious allergic reaction
• Worsening of diabetic eye disease (especially if you have low blood sugar)

The MHRA monitors the side effects of drugs in the UK and issues safety advice when required.

 

Which Is Better Tolerated?

Some say Mounjaro has less bothersome side effects, perhaps because GIP helps temper nausea. However, this is all depends to your body and how your provider is titrating your dose.

 

Wegovy vs Mounjaro Cost in the UK

Wegovy:

• Private Clinic Cost (monthly): £195–£295

Mounjaro:

• Private Clinic Cost (monthly): £215–£245

Private Clinics vs NHS Pathways

• Private Hospitals: Faster treatment, personal care but self paying.
• NHS: Only available for those with a Body Mass Index (BMI) over 35 and health problems. It has been made available in specialised NHS weight loss clinics since March 2025. An individual eligible to get the injection from NHS are with:
  • a BMI of 40 or more, or 37.5 if from a minority ethnic background.
  • any four of the following obesity related health conditions: type 2 diabetes, high blood pressure, heart disease, high cholesterol and obstructive sleep apnoea.

 

Insurance and Self-Pay Considerations

In the UK, most private health insurers will not cover weight loss injections. The majority either pay privately or via the NHS if they qualify.

 

Mounjaro vs Wegovy Reviews (Patient Reviews and Testimonials)

On health forums, clinic blogs and patient review sites, users have reported their own experiences to give one another a sense of what to expect.

Wegovy Reviews:

• Sarah, 43: “I was losing 20kg every 3 months. The nausea at the beginning was rough, but I adjusted to it.”
• James, 35: “Down 12kg feeling like I have control over food again. My cravings plummeted like crazy.”
• Emma, 51: “I no longer snack. I have lost over 2 stone in 4 months.

Mounjaro Reviews:

• Reddit user u/Baccarat76: “I lost 24kg in 14 weeks. It’s easy, I do not think about food anymore.”
• Bethany, 27 (UK): “I lost 5.5 stone in 9 months. It was helpful not only for my weight, but also my lipedema symptoms.”
• Jade, UK mum: 2.4 stone down in just under 4 months. More energy, better sleep.”

But this is not always the case. Clare, 52, said she had already lost only 7 lbs after five months on Mounjaro, and asked: “Is it worth the money?

 

Insights from Mounjaro vs Wegovy Reddit Discussions

UK based Reddit communities often share unfiltered reviews:

• Mounjaro users have been known to experience more powerful appetite suppressant results.
• Some switching to Mounjaro when they plateau on Wegovy.
• Many say Mounjaro’s GI side effects have been milder than they expected, but others are still fighting nausea.

Online reviews are useful, but not always consistent. A clinician visit ensures a safe, individual approach.

 

Mounjaro vs Wegovy for People with Type 2 Diabetes

If you have type 2 diabetes, and you are also trying to lose weight, a good option is choosing Mounjaro. It is indicated for healthy weight management as well as blood sugar control.

Wegovy, by contrast, is intended solely for weight loss, but its sister drug Ozempic is frequently prescribed to treat diabetes. Which one is the best depends on whether you are focused on greater weight loss, blood sugar, or both. Always contact a healthcare professional to help you decide.

 

Injection Frequency and Convenience

Both Mounjaro and Wegovy are administered only once a week, so you can easily add it to your regular routine. They are simple, pre-filled pens that do not require any mixing or measuring. The injections are quick, close to painless and simple to learn. If you are concerned you might give yourself an injection incorrectly, your clinic or pharmacist can teach you with confidence.

 

Availability in the UK

Wegovy is already available privately and on the NHS to those who qualify (based around a BMI above 35 if you have a weight-related condition).

Mounjaro is already available through private clinics and since March 2025 on the NHS. If you want to access it more quickly, or if you are not eligible according to NHS guidelines, a private clinic is your most likely source.

 

When to Choose Wegovy

For people who are looking for a highly researched and long established weight loss medication that is now accessible via the NHS for people who are suitably eligible, Wegovy may be the preferable alternative. You might be able to get NHS care if your BMI is more than 35 and you have other weight-related health conditions. Many users also have experienced Wegovy to have a smoother effect when starting out, which might mean that its initial side effects are not as intense. It is an excellent place to begin if you are new to weight loss injections and you are looking for something a bit more gentle.

 

When to Choose Mounjaro

If you are in search of a bit stronger appetite suppression, and the possibility of faster weight loss, Mounjaro may be best for you. It hits two hormones, so it is more potent for some users. It is perfect for the type 2 diabetic because it is clinically proven to aid weight loss and blood sugar. If you have already tried Wegovy, or another GLP-1 drug, and found yourself with no progress, Mounjaro might be able to push you along further.

 

Next Steps: Consult a Specialist Clinic

If you are thinking of beginning a weight loss injection, the first thing to do is to speak to your GP or a reputable weight loss clinic. They will be able to go over your medical history, see if you are eligible for NHS funded treatments and advise on the best plan of action for you. Private or NHS, the combination of the weight loss drugs with lifestyle changes such as healthier eating, reduce calorie intake, regular activity, is the best chance for long-term success. Remember that everyone’s weight loss journey is personalized and having help from professionals can really make a difference.

• Have an appointment with your GP or a private weight loss clinic
• Find out about what your choices are, what the side effects can be and whether you are eligible for NHS funding
• Have a strategic plan that is composed of lifestyle adjustments and regular follow up.

 

FAQs

• What’s the key differences between Mounjaro and Wegovy?

Mounjaro acts on two hormones related to hunger (GLP-1 and GIP), while Wegovy targets GLP-1 only. This could potentially make Mounjaro more effective weight loss medication, and lead to fat loss in some individuals.

• Which works better for weight loss: Mounjaro or Wegovy?

Mounjaro has had better results in trials, with some participants losing as much as 22.5% of their body weight. Wegovy assists the average person in losing about 15%.

• What are the side effects of Mounjaro vs Wegovy?

Both, when prescribed as a medicine, can lead to nausea, constipation, diarrhoea or feeling tired particularly during the early couple of weeks. These tend to improve on their own.

• How much do Wegovy and Mounjaro cost in the UK?

Wegovy is priced at approximately £195–£295 per month. Mounjaro is a bit pricier at £215–£245/month in private clinics.

• Is Mounjaro better tolerated than Wegovy?

Some consider Mounjaro to be more gentle on the stomach, others prefer Wegovy. That can vary depending on your body and dose.

• Can you switch from Wegovy to Mounjaro?

Yes, it would be possible to switch with medical supervision. Especially if you are using Wegovy and it stops working or has some issues.

• Is Mounjaro or Wegovy better for people with diabetes?

Although Mounjaro tackles weight by addressing blood sugar. Wegovy is limited to being a weight management

• Which injection is easier to use?

Both are simple, once a week pens that most people find easy to use.