Wegovy and Mounjaro are two prescription-only medicines that you may have heard about in relation to weight management. Although the two medicines have some similarities, they are not the same. They contain different active ingredients and work in slightly different ways within the body.
It is also important to remember that neither medicine is suitable for everyone. Prescription weight-management treatment should only be considered following an appropriate clinical assessment by a qualified healthcare professional.
In this guide, we explain some of the main differences between Wegovy and Mounjaro, how they work, how they are used and some of the factors a healthcare professional may consider when discussing weight-management treatment.
What Is Wegovy?
Wegovy is the brand name of a prescription-only medicine containing the active ingredient semaglutide. Semaglutide acts in a similar way to a naturally occurring hormone called glucagon-like peptide-1, commonly shortened to GLP-1. GLP-1 is involved in several processes within the body, including appetite regulation.
Wegovy is licensed for weight management alongside a reduced-calorie diet and increased physical activity in certain adults who meet specific body mass index (BMI) and health criteria. Whether it is suitable for an individual is something that needs to be determined through a clinical assessment.
What Is Mounjaro?
Mounjaro is the brand name of a prescription-only medicine containing tirzepatide. Tirzepatide acts on two hormone pathways known as GIP and GLP-1. These hormones are involved in processes including appetite, food intake and blood glucose regulation.
Mounjaro is licensed for weight management in certain adults who meet specific BMI and health criteria, alongside a reduced-calorie diet and increased physical activity. As with Wegovy, treatment requires an appropriate prescription and isn’t suitable for everyone.
What Is the Main Difference Between Wegovy and Mounjaro?
One of the main differences is their active ingredients and the hormone pathways they act upon. Wegovy contains semaglutide and acts on the GLP-1 receptor. Mounjaro contains tirzepatide and acts on both GIP and GLP-1 receptors. Although both medicines can form part of medically supervised weight management, they are different medicines and shouldn’t be considered interchangeable.
A healthcare professional will need to consider an individual’s health, medical history, other medicines and treatment requirements before determining whether prescription treatment is appropriate.
Are Wegovy and Mounjaro Both Prescription-Only Medicines?
Yes. Both Wegovy and Mounjaro are prescription-only medicines in the UK. This means they cannot simply be purchased in the same way as an over-the-counter medicine. Before prescription treatment can be supplied, an appropriately qualified healthcare professional must determine whether it is clinically suitable for the individual.
Who May Be Eligible for Prescription Weight-Management Treatment?
Eligibility depends on the medicine and the individual being assessed. For weight management, factors considered can include BMI and whether someone has weight-related health conditions. For example, licensed indications can include adults living with obesity, as well as some adults who are overweight and have at least one weight-related health condition.
However, BMI alone doesn’t determine whether a particular medicine is appropriate. A proper assessment also considers your wider health and medical history.
What Happens During a Weight-Management Consultation?
A weight-management consultation provides an opportunity for a healthcare professional to understand your circumstances before discussing appropriate options.
This can include reviewing factors such as:
- your current weight and BMI
- your medical history
- existing health conditions
- medicines you currently take
- previous approaches to weight management
- diet and physical activity
- your individual goals
- whether there are reasons a particular treatment may not be appropriate
The purpose of the consultation is to determine the most suitable approach for the individual, rather than to guarantee access to a particular medicine. Hodgson Pharmacy in Longfield provides private weight-management consultations where these factors can be discussed with an appropriate healthcare professional.
How Are Wegovy and Mounjaro Taken?
Both medicines have formulations used on a regular dosing schedule, but the exact instructions depend on the medicine and formulation prescribed. Treatment commonly begins at a lower dose and may be gradually adjusted. Dose changes are intended to be clinically managed rather than decided by the patient themselves.
Always follow the instructions provided by your prescriber and the patient information supplied with your medicine.
Why Are Doses Increased Gradually?
Starting at a lower dose and increasing treatment gradually can help the body adjust and may reduce the likelihood or severity of some gastrointestinal side effects. The appropriate dose and pace of any increase depend on the medicine and individual response.
You should never increase your dose faster than instructed by your healthcare professional.
What Side Effects Can Wegovy and Mounjaro Cause?
Like all medicines, Wegovy and Mounjaro can cause side effects.
Gastrointestinal side effects are among those commonly associated with these types of medicines and can include:
- nausea
- diarrhoea
- vomiting
- constipation
- abdominal discomfort
Not everyone experiences side effects, and their severity can vary considerably between individuals. There are also less common but potentially serious adverse effects associated with prescription medicines, which is why treatment should be appropriately prescribed and monitored.
Patients should read the patient information supplied with their prescribed medicine and speak to their healthcare professional if they experience concerning or persistent symptoms.
Pregnancy, Breastfeeding and Contraception
Neither Wegovy nor Mounjaro should be used during pregnancy or while breastfeeding. The MHRA advises that anyone taking these medicines who could become pregnant should use effective contraception. Semaglutide (Wegovy) should be stopped at least two months before trying for a baby, and tirzepatide (Mounjaro) at least one month before.
Mounjaro may also reduce the effectiveness of oral contraceptives in people who are overweight or living with obesity. The MHRA advises switching to a non-oral method of contraception, or adding a barrier method such as condoms, for four weeks after starting Mounjaro and for four weeks after each dose increase.
If you are pregnant, planning a pregnancy or breastfeeding, discuss this with the healthcare professional responsible for your care.
Why Are Diet and Exercise Still Important?
Prescription treatment isn’t intended to replace healthy lifestyle changes. Both medicines are licensed for weight management alongside dietary changes and increased physical activity in eligible patients. Developing sustainable habits around nutrition, movement and general health remains an important part of weight management.
Hydration can also be particularly important if treatment causes gastrointestinal symptoms such as vomiting or diarrhoea.
Is Mounjaro Better Than Wegovy?
There isn’t a universal answer to this question. They are different prescription medicines, and the most appropriate option depends on the individual. Someone else’s experience of a medicine, whether that’s a friend, family member or somebody discussing their treatment online, doesn’t determine whether the same medicine will be appropriate for you.
A healthcare professional can assess the relevant clinical factors and discuss suitable options.
Can I Switch Between Wegovy and Mounjaro?
You shouldn’t switch prescription weight-management medicines without discussing it with an appropriate healthcare professional. Changing medicines may require consideration of your current dose, treatment response, side effects, medical history and the appropriate timing of any change.
Never attempt to create your own switching or dosing schedule.
What If I Experience Side Effects?
If you’re prescribed weight-management medication and experience side effects, speak to the healthcare professional responsible for your treatment. They can assess your symptoms and advise on the appropriate next step. Seek urgent medical attention where symptoms are severe or you have been advised that a particular symptom requires urgent assessment.
Can I Buy Wegovy or Mounjaro Without a Prescription?
No. Wegovy and Mounjaro are prescription-only medicines in the UK. An appropriate healthcare professional needs to assess whether prescription treatment is suitable before it can be prescribed. Be cautious about websites or individuals offering prescription medicines without an appropriate consultation or prescription.
For information on private costs, read our guides How Much Does Wegovy Cost in the UK? and How Much Does Mounjaro Cost in the UK?
Weight-Management Consultations at Hodgson Pharmacy
Hodgson Pharmacy is an independent, GPhC-registered pharmacy based in Longfield, Kent. We provide private weight-management consultations for adults looking for professional support with managing their weight. A consultation allows an appropriate healthcare professional to review your individual circumstances, medical history and suitability for available weight-management options.
Weight-management support does not always involve prescription medicine. A consultation may identify other suitable approaches, including support with diet, physical activity and lifestyle changes.
The outcome of a consultation will depend on your individual clinical circumstances, and prescription treatment is not guaranteed. If you’d like more information about our weight-management consultations, you can get in touch with the pharmacy team.
Call 01474 707341 or email enquiries@hodgsonpharmacy.com.