In short
Overview
Eligibility for a GLP-1 is not a judgement call. There are three defined routes in, and one condition that applies before any of them.
Direct Answer
You are a candidate if you have not reached at least 5 per cent weight loss in three to six months with a proper lifestyle programme, and one of the following is true.
- BMI of 30 or above
- BMI of 27 to 29.9 plus a weight related condition
- Central adiposity, meaning a raised waist measurement, plus a weight related condition
The threshold is lower for people of Asian background, because BMI alone understates the risk of weight related complications in that group.
Who This Applies To
- Type 2 diabetes
- Abnormal cholesterol
- High blood pressure
- Heart disease
- Obstructive sleep apnoea
- Symptomatic osteoarthritis
- Fatty liver
- Mental health conditions
- Difficulty with physical function
- Anyone who has not yet tried a proper lifestyle programme for three to six months
- People who are pregnant
- People who are breastfeeding. Treatment is usually resumed once lactation has finished
- Anyone with a contraindication to the specific drug, which is assessed individually
Option Comparison / Decision Criteria
you will normally need the most effective agents, tirzepatide or semaglutide
the less effective agents, such as liraglutide or orforglipron, can often get you there
Why an In-Person Physician Review Matters
Why lifestyle first is not a formality Because behavioural intervention is the foundation of treatment, and it continues for everyone who starts medication rather than being replaced by it.
The three to six month period also establishes something useful: how you actually respond, and what is realistic to expect. Why the comorbidities are assessed properly Because several of them change which drug is chosen. Sleep apnoea: tirzepatide is particularly preferred, having shown improvement in sleep apnoea outcomes Established cardiovascular disease without diabetes: semaglutide is preferred, as the only agent with proven cardiovascular benefit in that group Type 2 diabetes: opens up additional options and changes the monitoring, since weight loss can cause low blood sugar on insulin or sulfonylureas What happens if it does not work There is a defined answer. Weight is monitored every two to three months, and if less than 4 to 5 per cent of body weight has been lost after 12 weeks at the maximum tolerated dose, the medication is normally stopped and a different agent tried. The exception is someone whose weight was climbing steadily and stopped climbing on treatment. That is a result even without loss, and treatment is often continued.
Frequently Asked Questions
Yes, in the sense that candidates are people who have not reached at least 5 per cent weight loss over three to six months with a comprehensive lifestyle programme. That phase also continues once medication starts.
Only if you also have a weight related condition, such as type 2 diabetes, high blood pressure, abnormal cholesterol, sleep apnoea, fatty liver or symptomatic osteoarthritis.
It can. Central adiposity with a raised waist measurement, plus a weight related condition, is one of the three recognised routes to eligibility.
For people of Asian background, yes. There is a lower threshold to start treatment, because BMI alone understates the risk of weight related complications in this group.
Evidence
Where this information comes from
Every figure on this page is taken from the sources below. All of them are free to read, so you can check them yourself.
- Wegovy: European public assessment report
- Mounjaro: European public assessment report
- Semaglutide for managing overweight and obesity
- Obesity and overweight
This page is general medical information and does not replace a personal consultation. Trial results are averages across large groups, not a prediction for any one person.