Tirzepatide eligibility in the UK: the criteria, the checks, and what happens next

Step 1: the BMI threshold, where eligibility starts, not ends

The UK licence for tirzepatide sets the primary BMI threshold at 30. If your BMI is between 27 and 29.9, you can still qualify, provided you have at least one weight-related condition alongside it. The conditions that count include type 2 diabetes, prediabetes, high blood pressure, dyslipidaemia (raised cholesterol or triglycerides), obstructive sleep apnoea, and osteoarthritis, among others. The BMI criteria for Mounjaro are set out in full if you want to work through your numbers before doing anything else.

One important detail: for people of South Asian, Chinese, other Asian, Middle Eastern, Black African, or African-Caribbean backgrounds, UK guidance applies BMI thresholds 2.5 kg/m² lower. So a threshold of 30 effectively becomes 27.5 for these groups, and so on. NICE's appraisal of tirzepatide reflects this adjustment throughout its recommendations for tirzepatide (TA1026).

Worth saying plainly: a BMI that meets the threshold is necessary but not sufficient. It's the entry point. Everything after it is clinical.

Step 2: the clinical review, what a prescriber actually looks at

Once you submit a consultation, a prescriber reads it. Not software, not a scoring algorithm, a named, GPhC-registered Independent Prescriber. They're looking at several things at once: your current BMI and weight history, any conditions you have, medicines you're already taking, and anything in your past that might affect how tirzepatide works or whether it's safe for you.

Certain contraindications require that conversation to happen carefully. A personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2 (MEN2) rules out tirzepatide entirely. A history of pancreatitis needs close scrutiny. Severe gastrointestinal conditions may also affect suitability. This is the kind of thing that doesn't show up in a BMI calculator, it's why the clinical review exists.

If you're already on treatment elsewhere and want to transfer, evidence of your current dose is required. Dose increases similarly need a clinical basis. Our clinical team can walk you through what that looks like for your situation. The NHS's tirzepatide medicines page also lists contraindications and interactions in plain language if you want to read ahead.

Step 3: situations that change the answer, pregnancy, other medicines, and NHS vs private

Tirzepatide is not recommended during pregnancy, and is not suitable for people who are breastfeeding or actively trying to conceive. The wash-out period before attempting conception is something to discuss with your prescriber directly. If you're unsure whether any of this applies to you, our page covering who can take tirzepatide works through the key suitability questions in plain terms. The treatment is also not licensed for anyone under 18.

Drug interactions matter too. If you're taking oral contraceptives, tirzepatide can affect how quickly the pill is absorbed; for the first four weeks of treatment and for four weeks after each dose increase, an additional non-oral contraceptive method is recommended. NHS England's guidance on weight management injections covers this clearly. For anyone on HRT, transdermal forms (patches or gels rather than tablets) are worth discussing with your doctor for the same reason.

On the NHS, tirzepatide access is currently phased and tightly criteria-driven, Cohort 2 opened in June 2026 for people with a BMI of 35–39.9 and four or more qualifying conditions. Private treatment through a regulated pharmacy like ours is a separate route, with the same clinical rigour but no waiting list, subject to your suitability being confirmed. You can read more about the full Mounjaro eligibility criteria in the context of both routes if that distinction matters for your decision.

Step 4: what happens if you're not eligible right now

Not everyone who asks turns out to be a candidate for tirzepatide immediately, and the honest answer, if that's where you land, is that a prescriber will tell you why and what the alternatives might be. Sometimes it's a BMI that's close but not quite there with the conditions listed. Sometimes it's a contraindication that rules it out for now. Sometimes the picture becomes clearer with a GP conversation first.

For people who are eligible in principle but weighing up their options, the cost of Mounjaro is one practical consideration. Our weight loss treatment overview covers what else is available through nume (sorry, through our service) for those exploring what fits. One question our prescribers hear most weeks is whether someone qualifies, and our guide to Mounjaro eligibility is a good place to work through that before committing. The free consultation exists precisely for that. There's no obligation, and the same-day clinical review gives you a straight answer.

If you're ready to find out where you stand, speak to our prescribers, it starts with a free consultation, and the clinical team reviews it the same day.