In the UK you may be eligible for weight loss injections if you are aged 18 or over and have a BMI of 30 or above, or a BMI of 27–30 alongside a weight-related health condition such as type 2 diabetes, high blood pressure or sleep apnoea. Eligibility is confirmed only after a clinical consultation with a GPhC-registered prescriber, who checks the treatment is safe and appropriate for you.
Below you will find the exact criteria, the conditions that mean these medicines are not suitable, and what actually happens when you complete an online check.
The core eligibility criteria
Weight loss injections such as Mounjaro (tirzepatide) and the Wegovy injection (semaglutide) are prescription-only medicines. The same eligibility rules apply across these injectables and the oral options we offer.
To be considered, you generally need to meet all of the following:
- You are aged 18 or over.
- Your BMI is 30 or above (classed as obesity), or
- Your BMI is 27 to 30 and you have a weight-related condition — for example type 2 diabetes, high blood pressure or obstructive sleep apnoea.
BMI (body mass index) is a simple screen using your height and weight. It is a starting point rather than the whole picture — a prescriber looks at your overall health, not the number alone.
How to work out your BMI
Divide your weight in kilograms by your height in metres squared. For example, someone who is 1.7m tall and weighs 90kg has a BMI of about 31 (90 ÷ (1.7 × 1.7)). If you are between the 27 and 30 threshold, having a qualifying health condition is what makes treatment appropriate.
Who is not suitable for weight loss injections
Meeting the BMI threshold does not automatically mean these medicines are right for you. A treatment is not suitable if any of the following apply:
- You are pregnant, planning a pregnancy, or breastfeeding.
- You have type 1 diabetes.
- You or a close family member has a history of medullary thyroid carcinoma, or you have MEN2 (a rare hormonal syndrome).
- 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 the active ingredient.
This is why an online questionnaire alone cannot approve you. A prescriber reviews your medical history, current medicines and any red flags before deciding whether to prescribe.
What the eligibility check involves
At The Weight Clinic the online consultation is free, and you only pay if a treatment is prescribed and you choose to go ahead. The process 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.
- Where clinically needed, you have a short video consultation.
- 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. Being honest and complete on your questionnaire keeps the process safe.
Which treatments might you be eligible for?
If you meet the criteria, several options may be discussed. They share the same eligibility rules but differ in how they work and how they are taken.
| Treatment | Type | How taken | From (per month) |
|---|---|---|---|
| Mounjaro (tirzepatide) | GLP-1 and GIP receptor activator | Weekly injection | £160 |
| Wegovy injection (semaglutide) | GLP-1 receptor agonist | Weekly injection | £115 |
| Wegovy Tablet (oral semaglutide) | GLP-1 receptor agonist | Once-daily tablet on an empty stomach | £115 |
| Foundayo (orforglipron) | Small-molecule GLP-1 tablet | Once-daily tablet, any time, with or without food | £115 |
You can see the full range on our treatments overview or the combined weight loss injections page. The prescriber will help match a suitable option to your circumstances.
A note on what the trials showed
In the SURMOUNT-1 trial, participants on the Mounjaro 15mg dose lost on average 22.5% of body weight over 72 weeks, alongside lifestyle support. In the STEP UP trial, adults on the Wegovy 7.2mg dose lost on average 20.7% of their body weight over 72 weeks, alongside lifestyle support. Individual results vary; not everyone reaches this.
Side effects to be aware of
Because these medicines share a similar class of action, they share a similar side effect profile. The most common effects (affecting more than 1 in 10 people) include nausea, diarrhoea, constipation, vomiting, decreased appetite and fatigue. These often ease as your body adjusts and as doses are increased gradually.
Rare but serious effects can include severe allergic reaction, acute pancreatitis, severe hypoglycaemia, severe gastrointestinal disease and worsening diabetic retinopathy. If you experience side effects, you can report them through the MHRA Yellow Card scheme at https://yellowcard.mhra.gov.uk/.
How to check whether a clinic is legitimate
Only use a service that dispenses through a GPhC-registered UK pharmacy. Our medicines are dispensed by our own pharmacy, North Harrow Pharmacy (GPhC registration 1034996), which you can verify on the General Pharmaceutical Council register at pharmacyregulation.org. We supply only genuine, MHRA-licensed medicines. You can read more about The Weight Clinic or contact us with questions.
Ready to find out?
The quickest way to answer "am I eligible?" is to complete the free check — it takes a few minutes and there is no obligation. Start your free consultation and a registered prescriber will review whether treatment is right for you. For more reading, browse our blog.
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.
