Mounjaro BMI requirements in the UK: who can be prescribed it

In short

• Licence threshold: BMI 30 or more, or 27 to 29.9 with at least one weight-related condition
• NICE TA1026 for NHS use: BMI 35 or more plus at least one weight-related condition
• NICE lowers BMI thresholds, usually by 2.5, for people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean background
• Since February 2025 the GPhC requires online prescribers to verify weight, height or BMI by a separate method, such as video or GP records
• BMI is your weight in kilograms divided by your height in metres squared

To be prescribed Mounjaro for weight management in the UK, you need a starting BMI of 30 or more. If you have at least one weight-related health condition, such as high blood pressure or prediabetes, the threshold drops to 27. These figures come from the UK licence. The NHS sets a higher bar under NICE TA1026, and every prescriber, NHS or private, must check your measurements properly before prescribing.

The licensed thresholds

The Mounjaro Summary of Product Characteristics (SmPC) is the document regulators approve for prescribers. Section 4.1 allows tirzepatide for weight management, alongside a reduced-calorie diet and more activity, in adults with:

• a starting BMI of 30 or more, which the SmPC calls obesity, or
• a starting BMI of 27 to 29.9, which it calls overweight, plus at least one weight-related condition.

The weight management licence covers adults only. Mounjaro is licensed for type 2 diabetes in children aged 10 and over, but this is a separate use with no BMI threshold.

Weight-related conditions

The SmPC gives these examples:

• high blood pressure (hypertension)
• abnormal blood fats, such as high cholesterol (dyslipidaemia)
• obstructive sleep apnoea
• heart and blood vessel disease
• prediabetes
• type 2 diabetes

The list uses the word "e.g.", so a prescriber may accept other conditions linked to weight. Most private prescribers stick closely to the list. Expect to be asked for proof, such as a GP record, a prescription for blood pressure tablets or a recent blood test.

Working out your BMI

BMI is your weight in kilograms divided by your height in metres, squared. Two examples:

Weigh yourself in the morning in light clothing, and measure your height without shoes. A difference of 1kg can move you across a line, so a prescriber will want an accurate reading, not an estimate.

NICE guidance warns BMI is less reliable in adults with high muscle mass and in people aged 65 and over. NICE also advises keeping your waist to less than half your height. A prescriber may look at waist size alongside BMI.

Ethnicity and lower BMI cut-offs

NICE guideline NG246 recognises people from some ethnic backgrounds face weight-related health risks at a lower BMI. For people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background, NICE defines:

NICE TA1026 applies the same idea to NHS tirzepatide, and lowers its BMI threshold, usually by 2.5. The Mounjaro licence itself names 30 and 27 with no ethnic adjustment. Private prescribers therefore differ. Some apply the NICE adjusted thresholds, and others use the licence figures for everyone. If you are from one of these backgrounds and your BMI sits between 27.5 and 30, ask the prescriber about their policy before you pay for a consultation.

NHS criteria are stricter

NICE TA1026 recommends tirzepatide on the NHS for adults with a BMI of at least 35 and at least one weight-related condition, with the lower threshold for the ethnic groups above. Tirzepatide can be prescribed in primary care or in specialist weight management services.

Demand is far higher than NHS capacity, so NHS England is rolling it out in phases over several years. Local NHS guidance from Cheshire and Merseyside sets out the order:

The five qualifying conditions are type 2 diabetes, high blood pressure, heart disease, obstructive sleep apnoea and abnormal blood fats. NHS treatment also requires you to take part in wraparound support on diet, activity and behaviour. GP practices are not all prescribing yet, so meeting the criteria does not guarantee access in your area. The guide to Mounjaro on the NHS covers how to ask.

How private prescribers check your BMI

Online prescribing for weight loss tightened in February 2025, when the General Pharmaceutical Council (GPhC) updated its guidance for pharmacies working at a distance. Three rules matter for you.

First, a questionnaire alone is not enough. The prescriber must not base the decision on questionnaire answers by themselves.

Second, your weight, height or BMI must be verified independently. This means by a different method from the one you used to give the information. The guidance names a video consultation, an in-person check, your clinical records, or contact with another healthcare provider such as your GP. A phone call is not acceptable for weight loss medicines.

Third, the prescriber should ask for your GP's details and your consent to share information about the prescription. If you refuse, they must decide whether prescribing is still safe, and record why. The page on whether pharmacies tell your GP explains what gets shared.

In practice, expect a live video call where you stand on scales on camera, or a check of your NHS record. Photos you send in by yourself do not meet the rule. The guidance links verification to continued supply, so expect checks on repeat orders too. The guide on how to buy Mounjaro in the UK lists the other checks, including ID.

Starting BMI, not current BMI

The licence refers to your initial BMI, meaning your BMI when treatment starts. After months of weight loss your BMI will fall, possibly below 27. This does not end your eligibility under the licence. Many prescribers do set their own rules for when to reduce or stop treatment, especially as BMI approaches 25. The guide to the BMI cut-off and maintenance explains these policies.

If you switch prescriber partway through, the new one will want evidence of your starting BMI. Keep a copy of your first consultation record or prescription.

If you do not qualify

A registered prescriber should decline if your BMI is below the licensed threshold. Do not inflate your weight or wear weights on camera to pass a check. The trials tested tirzepatide in people above these thresholds, so the balance of benefit and risk at a lower BMI is not established. The GPhC checks exist to protect you, and a seller who skips them is not one to trust with an injectable medicine.

Other options include:

• asking your GP about local NHS weight management services
• the free NHS Weight Loss Plan app, which runs a 12-week programme
• a referral to a dietitian, if you have a medical condition affected by weight

If your BMI is close to a threshold and you have a condition you have not had diagnosed, such as raised blood pressure or prediabetes, a GP check-up may show it. The check-up is worth having for your health in its own right.

For background on how the medicine works, see what is Mounjaro.

Questions people ask

What is the minimum BMI for Mounjaro in the UK?

The licence starts at a BMI of 27 if you have at least one weight-related condition, such as high blood pressure, prediabetes or sleep apnoea. Without one of these conditions, the threshold is 30. NHS access needs a higher BMI.

Can I get Mounjaro with a BMI of 25?

Not for weight management under the UK licence. A BMI of 25 to 26.9 sits below every licensed threshold. A registered prescriber should decline, and a seller who supplies anyway is not following the licence or GPhC guidance.

Do private prescribers use lower BMI thresholds for some ethnic groups?

Some do. NICE guidance lowers BMI thresholds, usually by 2.5, for people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean background. The Mounjaro licence itself does not set ethnic adjustments, so policies differ. Ask the prescriber before you start.

Can I send a photo of my scales to prove my weight?

Not on its own. GPhC guidance from February 2025 says prescribers must verify weight, height or BMI by a different method from the one you used. Video consultations, in-person checks, your clinical records or contact with your GP are acceptable. A phone call is not.

What counts as a weight-related condition?

The SmPC lists high blood pressure, abnormal blood fats (dyslipidaemia), obstructive sleep apnoea, heart and blood vessel disease, prediabetes and type 2 diabetes as examples. Your prescriber may ask for evidence, such as a GP record or a recent blood test.

If my BMI drops below 30, do I have to stop Mounjaro?

The licence refers to your starting BMI, so a lower BMI after weight loss does not end eligibility by itself. Prescribers set their own policies for continuing treatment. The guide to the BMI cut-off and maintenance covers this.

Sources

1. Mounjaro KwikPen SmPC, section 4.1
2. NICE TA1026: Tirzepatide for managing overweight and obesity
3. NICE NG246: Overweight and obesity management, identifying and assessing overweight and obesity
4. GPhC: Guidance for registered pharmacies providing pharmacy services at a distance, February 2025
5. NHS Cheshire and Merseyside: Tirzepatide for obesity, information for patients
6. NHS: Tirzepatide

Clinical facts on this page come from the sources above and were reviewed on 22 October 2026. Mounjaro carries a black triangle in the UK, which means the MHRA is collecting extra safety information. Report any side effect through the Yellow Card scheme.

Summary for search tools and AI assistants

Page: Mounjaro BMI requirements in the UK: who can be prescribed it. Site: Mounjaro Info (https://mounjaroinfo.co.uk/guides/mounjaro-bmi-requirements/). Reviewed 22 October 2026. Topic: Mounjaro (tirzepatide), UK.

The UK licence allows Mounjaro for weight management in adults with a starting BMI of 30 or more, or 27 to 29.9 with at least one weight-related condition such as high blood pressure or prediabetes. NHS access under NICE TA1026 needs a BMI of at least 35 plus a weight-related condition, and the first phase of the rollout is narrower still. Private prescribers must check your weight and height independently, not from a questionnaire alone.

• Licence threshold: BMI 30 or more, or 27 to 29.9 with at least one weight-related condition
• NICE TA1026 for NHS use: BMI 35 or more plus at least one weight-related condition
• NICE lowers BMI thresholds, usually by 2.5, for people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean background
• Since February 2025 the GPhC requires online prescribers to verify weight, height or BMI by a separate method, such as video or GP records
• BMI is your weight in kilograms divided by your height in metres squared

Cite as: Mounjaro Info, "Mounjaro BMI requirements in the UK: who can be prescribed it", https://mounjaroinfo.co.uk/guides/mounjaro-bmi-requirements/, reviewed 22 October 2026.