With so many weight loss injections now available, it is completely understandable to feel confused about which is which. Wegovy and Mounjaro are two of the most prescribed options in the UK right now, and many people assume they are interchangeable. They are both weekly injections, both used for weight management, and both have strong clinical backing. However, they contain different active ingredients, work through different mechanisms, and are not the same medication.

If you are trying to decide which treatment is right for you, getting clear on the differences is a good first step. At Shivas Pharmacy, we support patients through every stage of their weight management journey. Contact us today or book an appointment with our team to discuss your options.

What Is Wegovy?

Wegovy contains semaglutide, a GLP-1 receptor agonist. It works by mimicking a gut hormone that signals fullness to the brain, slowing gastric emptying and reducing overall appetite. It is licensed in the UK specifically for weight management in adults who are living with obesity or who are overweight with a related health condition such as high blood pressure or type 2 diabetes.

Wegovy is administered as a once-weekly subcutaneous injection. Treatment begins at a low dose of 0.25mg and gradually increases over several months to a maintenance dose of 2.4mg, allowing the body to adjust and helping to reduce side effects during the early stages.

What Is Mounjaro?

Mounjaro contains tirzepatide, which works differently from semaglutide. Rather than targeting only the GLP-1 receptor, tirzepatide is a dual-action medication that activates both GLP-1 and GIP receptors. GIP is a second gut hormone involved in regulating fat storage and blood sugar. By targeting both receptors simultaneously, Mounjaro produces a broader metabolic effect. Learn more using our detailed guide on where to administer your Mounjaro dosage.

Mounjaro is licensed in the UK for both type 2 diabetes management and weight management. Like Wegovy, it is a once-weekly injection, starting at 2.5mg and increasing gradually to a maximum of 15mg. You can read more about how it works on the NHS tirzepatide page.

How Do They Compare Side By Side?

Both medications are weekly injections used for weight management, but several important differences set them apart. The table below summarises the key points.

Feature	Wegovy	Mounjaro
Active ingredient	Semaglutide	Tirzepatide
How it works	GLP-1 receptor agonist	Dual GLP-1 and GIP receptor agonist
Starting dose	0.25mg weekly	2.5mg weekly
Maximum dose	2.4mg weekly	15mg weekly
UK licensed use	Weight management	Weight management and type 2 diabetes
Injection frequency	Once weekly	Once weekly

Which One Produces Better Results?

Clinical trials have shown that both medications produce meaningful weight loss when used alongside dietary changes and increased activity. Mounjaro’s dual receptor action has generally shown greater average weight loss in head-to-head comparisons, but this does not mean it is automatically the better choice for every individual.

Response to these medications is highly personal. Some people do exceptionally well on semaglutide, while others find tirzepatide suits them better. Factors such as tolerability, existing health conditions, and how your body responds to treatment all matter more than any single figure from a clinical trial. You can browse our guide to understand how much weight you can lose on Mounjaro.

Do They Have The Same Side Effects?

Because both medications act on similar receptors, their side effect profiles are comparable. The most commonly reported effects for both are gastrointestinal, particularly in the early weeks of treatment. These typically ease as the body adjusts to the medication.

Common side effects for both include:

■  Nausea	■  Vomiting	■  Diarrhoea
■  Constipation	■  Indigestion or bloating	■  Fatigue or dizziness

If side effects feel difficult to manage at any point, speak to your pharmacist or prescriber rather than stopping treatment abruptly.

Which One Should You Choose?

There is no universal answer. Both treatments are clinically effective and licensed for use in the UK. A prescriber will consider your full health profile before recommending either option, including whether you have type 2 diabetes, any history of pancreatitis, kidney or liver conditions, and what your previous experience with weight management has been.

The most important step is speaking to a qualified professional rather than making a decision based on general information alone. Our team at Shivas Pharmacy can guide you through both options clearly and help you arrive at a treatment plan that suits your individual circumstances. Get in touch with us or book your appointment today.

Frequently Asked Questions

Is Wegovy the same as Mounjaro?

No. Wegovy contains semaglutide and targets only the GLP-1 receptor. Mounjaro contains tirzepatide and targets both GLP-1 and GIP receptors. They are different medications with different active ingredients, although both are used for weight management.

Which is stronger, Wegovy or Mounjaro?

Clinical trials suggest Mounjaro produces greater average weight loss due to its dual receptor action. However, individual results vary considerably, and the right treatment depends on your personal health profile, not just clinical averages.

Can you switch from Wegovy to Mounjaro?

It is possible to switch between the two, but this should always be done under the guidance of a healthcare professional. The dosing schedules differ, and an appropriate transition plan is important to minimise side effects and maintain progress.

Are the side effects of Wegovy and Mounjaro the same?

The side effect profiles are similar, with both medications most commonly causing gastrointestinal symptoms such as nausea, vomiting, and diarrhoea. These tend to be most pronounced at the start of treatment or after a dose increase and usually settle with time.

Can I get Wegovy or Mounjaro at Shivas Pharmacy?

Yes. Shivas Pharmacy offers weight management consultations and can support you in accessing the right treatment based on your needs. Book an appointment with our team to get started.

Start Your Weight Management Journey With Shivas Pharmacy

Whether you are considering Wegovy, Mounjaro, or simply want to better understand your options, our team is here to provide clear, personalised guidance. We take the time to understand your health history and goals so that any treatment we support you with is appropriate, safe, and well-monitored throughout.

If you are looking for weight management support in Surrey, contact us today and book your appointment with Shivas Pharmacy so we can help you move forward with confidence.

This blog was written on behalf of Shivas Pharmacy by Pharmacy Mentor.