In the UK, you may be eligible for Mounjaro (tirzepatide) if you are aged 18 or over and have a BMI of 30 or more, or a BMI of 27–30 with a weight-related health condition such as type 2 diabetes, high blood pressure or sleep apnoea. It is a Prescription-Only Medicine, so it can only be supplied after a clinical consultation with a GPhC-registered prescriber who confirms it is safe and appropriate for you.
Below is the full UK eligibility picture — the criteria that let you qualify, the factors that rule it out, and how a proper assessment works. This is educational information, not a guarantee that treatment will be prescribed.
The core eligibility criteria
The criteria for Mounjaro when prescribed for weight management are consistent with other GLP-1 based treatments. You generally need to meet all of the following:
- You are aged 18 or over.
- Your BMI is 30 or above (which falls in the obesity range), or
- Your BMI is between 27 and 30 and you have a weight-related health condition — for example type 2 diabetes, high blood pressure or obstructive sleep apnoea.
These thresholds exist because the potential benefits of treatment are weighed against the risks. Above these BMI points, excess weight is more likely to be affecting your long-term health, which is why the medicine may be considered.
How to work out your BMI
BMI (body mass index) is your weight in kilograms divided by your height in metres squared. It is a screening tool rather than a perfect measure — it does not distinguish muscle from fat, and it does not account for factors like ethnicity or body composition on its own.
For that reason, a prescriber looks at your BMI alongside your wider health rather than treating a single number as the whole answer. During a consultation your measurements and history are reviewed together.
Who Mounjaro is not suitable for
Even if you meet the BMI criteria, Mounjaro is not suitable for everyone. A prescriber will not issue it if any of the following apply:
- You are pregnant, planning pregnancy, or breastfeeding.
- You have type 1 diabetes.
- You have a personal or family history of medullary thyroid carcinoma, or the genetic condition MEN2.
- You have a history of pancreatitis.
- You have severe gastrointestinal disease.
- You have an active eating disorder.
- You have severe liver or kidney impairment.
- You have a known allergy to tirzepatide or any of the ingredients.
These exclusions are about safety. Some describe situations where the medicine could cause harm, and others describe conditions where the risks are not well enough understood to prescribe responsibly.
Mounjaro on the NHS vs a private online service
Access to Mounjaro on the NHS is being introduced gradually and is subject to strict prioritisation — typically for people with a higher BMI and additional health conditions, often through specialist services, and usually with waiting periods. Availability and criteria depend on national and local rollout plans.
A regulated private service such as The Weight Clinic follows the same clinical eligibility principles but can assess you directly through an online consultation. Either route uses the same genuine, MHRA-licensed medicine and the same prescribing safeguards.
You can read more about the medicine itself on the Mounjaro page, or compare it with other options on the treatments overview.
What makes Mounjaro different
Mounjaro contains tirzepatide, which activates two gut-hormone receptors — GLP-1 and GIP — at the same time. Working on both pathways is what distinguishes it from single-hormone options such as the Wegovy injection or the Wegovy Tablet.
In the SURMOUNT-1 trial, participants on the 15mg dose lost on average 22.5% of body weight over 72 weeks, alongside lifestyle support. Individual results vary; not everyone reaches this. Citation: Jastreboff AM, et al. N Engl J Med. 2022;387(3):205–216.
Mounjaro is taken as a weekly self-injection and the dose is increased gradually — starting at 2.5mg, then stepping up through 5mg, 7.5mg, 10mg and 12.5mg to a maximum licensed dose of 15mg. This slow titration helps your body adjust and can reduce side effects.
Side effects to be aware of
Understanding the side effects is part of deciding whether treatment is right for you. The most common effects (affecting more than 1 in 10 people) are nausea, diarrhoea, constipation, vomiting, decreased appetite and fatigue. These are often most noticeable early on or after a dose increase.
Rare but serious risks include severe allergic reaction, acute pancreatitis, severe hypoglycaemia (low blood sugar), severe gastrointestinal disease, and worsening of diabetic retinopathy. If you experience severe or persistent symptoms, seek medical advice.
You can report suspected side effects through the MHRA Yellow Card scheme at https://yellowcard.mhra.gov.uk/.
The cost if you are eligible
If treatment is prescribed and you choose to proceed, Mounjaro is priced by dose. The consultation itself is free.
| Dose | Price per month |
|---|---|
| 2.5mg (starter) | £160 |
| 5mg | £185 |
| 7.5mg | £240 |
| 10mg | £260 |
| 12.5mg | £275 |
| 15mg | £295 |
The cheapest starting dose is £160 per month. You only pay if a treatment is prescribed and you decide to go ahead.
How the eligibility check works
Confirming eligibility is a clinical process, not a self-declaration. At The Weight Clinic it works like this:
- You complete a free online consultation about your health, weight and medical history.
- A GPhC-registered independent prescriber reviews your answers to check treatment is clinically appropriate and safe.
- A short video consultation is arranged where clinically needed.
- If suitable, the medicine is dispensed by our own UK pharmacy and sent by tracked delivery, with ongoing prescriber support.
A prescription is only issued if it is clinically appropriate — treatment is never guaranteed. If Mounjaro is not right for you, a prescriber may discuss other options.
Not yet available in the UK, Foundayo (orforglipron) is a once-daily pill under MHRA review, which we will offer once it is licensed.
Ready to find out if you qualify?
The quickest way to get a clear answer is to complete the free eligibility check. It takes a few minutes and puts your details in front of a registered prescriber. You can also learn more about The Weight Clinic or contact us with any questions.
This article is for information only and is not a substitute for personalised medical advice. Weight-loss medicines are prescription-only, are not suitable for everyone, and are prescribed only after a clinical consultation with a GPhC-registered prescriber. Individual results vary. Always speak to a UK-registered pharmacist or doctor before starting or changing any prescription medication.
