The eligibility criteria for orforglipron are the same ones used across weight-management medicines in the UK, which makes them easy to state and easy to misread. Meeting a BMI threshold is the entry point to a clinical assessment, not a decision in itself, and the gap between those two things accounts for most of the confusion people encounter.
The authorised criteria
The MHRA authorised orforglipron for weight loss and weight maintenance in adults with a body mass index of 30 or above, or a body mass index between 27 and 30 accompanied by at least one weight-related health condition. In both cases it is authorised for use alongside a reduced-calorie diet and increased physical activity, which is part of the authorisation rather than a suggestion attached to it. Separately, it is authorised to improve blood sugar control in adults whose type 2 diabetes is not adequately controlled, which is a distinct indication with its own reasoning.
What counts as a weight-related condition
For people in the 27 to 30 band, the accompanying condition is what brings them within the criteria. The conditions usually meant here are type 2 diabetes, prediabetes, high blood pressure, obstructive sleep apnoea, raised cholesterol or other dyslipidaemia, and cardiovascular disease. Conditions such as osteoarthritis affected by weight, polycystic ovary syndrome and fatty liver disease may also be relevant depending on the assessment. The logic is that at this level of body weight the medicine is justified by the health condition it is likely to improve, rather than by the weight figure alone.
Why meeting the criteria is not the same as being suitable
This is where most people's expectations part company with how prescribing actually works. Orforglipron is a prescription-only medicine, so the criteria determine who may be considered, and a clinical assessment determines who should be treated. That assessment covers your full medical history, everything else you take, whether you are pregnant, breastfeeding or planning to conceive, any history of pancreatitis or gallbladder disease, thyroid history, diabetic eye disease, and your experience of any previous GLP-1 treatment. There are people who comfortably clear the BMI threshold for whom this particular medicine is the wrong choice, and there are people for whom a different treatment in the same class is a better fit.
Who it is not for
It is not authorised for children, and it is not for use in pregnancy or while trying to conceive, so contraception is part of the conversation for anyone who could become pregnant. Anyone with a history of pancreatitis, significant gallbladder disease, severe gastrointestinal disease or certain thyroid conditions needs that weighed carefully. People taking insulin or a sulfonylurea for type 2 diabetes can take it, but those doses may need adjusting because the combination can push blood sugar too low. And it is not a treatment for people seeking cosmetic weight loss below the authorised thresholds, which is the request prescribers decline most often.
The part that is not about criteria at all
Weight-management medicines work as long-term treatment, and the evidence across this class is consistent that appetite returns and weight tends to be regained once treatment stops. That makes readiness a genuine part of eligibility, even though it appears on no criteria list. Being willing to engage with the dietary changes, to protect muscle through protein and some resistance exercise, to attend reviews, and to think in terms of years rather than a course of treatment all shape whether the medicine will actually deliver anything durable. A good assessment asks about this, and it is worth having thought about it beforehand.
The timing problem
There is an unavoidable practical caveat to all of this. Orforglipron was authorised on 10 August 2026 but is not yet available in the UK, on the NHS or privately, and no launch date has been confirmed. NICE is due to publish guidance on NHS use on 18 November 2026. So eligibility for orforglipron specifically is currently a hypothetical question. If you meet the criteria and want treatment now, the productive step is an assessment against the treatments that are available today, which use the same thresholds, rather than waiting for a product with no confirmed arrival date. If orforglipron then turns out to suit you better, switching is a conversation to have at that point.
If you do not meet the criteria
Falling below the thresholds is a common outcome and not a dead end. For people whose BMI sits in the 27 to 30 band without a qualifying condition, an assessment may identify one that had not been recognised, since raised blood pressure, prediabetes and sleep apnoea frequently go undiagnosed. For those below 27, the honest answer is that GLP-1 medicines are not the appropriate route, and the evidence-based options are the less headline-grabbing ones: structured dietary change, resistance training to protect and build muscle, sleep and alcohol, and addressing anything driving weight gain such as a thyroid problem or a medicine with weight gain as a side effect. That is a less satisfying answer than a prescription, but it is the accurate one, and the risks of obtaining a prescription-only medicine outside a proper assessment are substantial.
What an assessment involves
In practice it means a consultation covering height and weight, medical history, current medicines, previous weight-management attempts and what happened with them, and any relevant family history. Blood tests are sometimes appropriate, particularly where type 2 diabetes or thyroid function is in question. The outcome is a judgement about whether a weight-management medicine is appropriate at all, and if so which one, at what starting dose, and with what monitoring. That is a more useful conversation than a BMI calculation, and it is the one that determines the answer.
