The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
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Weight Loss Support Near You in the UK
If you're searching for weight loss support near you in the UK, you have several options available — from NHS specialist services to private prescription pathways. Prescription weight management medications like Mounjaro and Wegovy are now accessible to eligible adults across the UK, alongside traditional diet and exercise support. Whether you want to work with your GP, access NHS weight loss programmes, or explore private online prescribing, this guide explains what's available and how to get started.
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Calculate Your BMI Instantly
Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
UK-Licensed Prescription Weight Loss Medications
Three prescription-only weight management medications are currently licensed in the UK for eligible adults: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). These prescription weight loss options work by mimicking natural hormones that regulate appetite and help you feel fuller after eating.
Eligibility for prescription weight management typically includes:
- BMI of 30 or above, or
- BMI of 27–29.9 with weight-related health conditions (type 2 diabetes, high blood pressure, sleep apnoea, cardiovascular disease)
- For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds (27.5+) may apply
Clinical trials show that alongside reduced-calorie diet and increased physical activity, these medications may help adults lose an average of 14–21% of their body weight — though individual results vary significantly. Our GLP-1 weight loss calculator can help you explore potential outcomes at different dose levels.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
How to Access Weight Loss Treatment in the UK
You have two main pathways: NHS specialist weight management services or private online prescribing. Through the NHS, your GP can refer you to tier 3 or tier 4 specialist weight management services if you meet clinical criteria — though waiting lists vary significantly by region and can extend several months. Private online prescribing offers faster access: licensed prescribers assess your health via online consultation, and if appropriate, issue a prescription dispensed by a GPhC-registered pharmacy.
Whichever route you choose, start by speaking with your GP about your weight loss goals. They can assess your health, discuss medication suitability, and either refer you to NHS services or provide guidance on private options. Use our free BMI calculator to check your starting point, and our progress tracker to monitor your journey once treatment begins.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
How do I know if I'm eligible for prescription weight loss medication in the UK?
You're typically eligible if you have a BMI of 30 or above, or 27–29.9 with a weight-related health condition like type 2 diabetes, high blood pressure, or cardiovascular disease. South Asian, Chinese, Black African, and Black Caribbean adults may be eligible from BMI 27.5. Check your BMI using our free calculator, then speak with your GP about eligibility.
What's the difference between NHS and private weight loss treatment?
NHS access is through specialist tier 3/4 services (referral from your GP) but waiting lists vary by region. Private online prescribing offers faster access through licensed prescribers and GPhC-registered pharmacies, without an NHS referral — typically costing £129–£320 monthly depending on dose. Both require clinical assessment.
How much weight can I expect to lose with Mounjaro or Wegovy?
Clinical trials show average weight loss of 14–21% of body weight over 68–72 weeks, alongside dietary changes and exercise. Individual results vary significantly — some people lose more, others less. Your progress depends on dose, adherence, lifestyle changes, and individual factors. Track your progress with our free progress tracker.
Can my GP prescribe Mounjaro or Wegovy directly, or do I need a specialist referral?
Most GPs refer eligible patients to NHS specialist weight management services (tier 3/4) where medication is prescribed. However, you can also access prescription weight loss privately via online prescribers without an NHS referral. Ask your GP about both options and what's available in your area.
Are these weight loss injections available on the NHS?
Yes — tirzepatide (Mounjaro) and semaglutide (Wegovy) are approved for NHS use through specialist tier 3/4 weight management services, but availability and waiting times vary significantly by region and local ICB funding. Your GP can refer you if you meet eligibility criteria, though private access may be faster.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.