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 Camp: UK Prescription Medication Options
While traditional weight loss camps focus on intensive residential programmes, many UK adults are now exploring prescription weight management options as an alternative approach to sustainable weight loss. If you're considering structured support for weight management, there are several evidence-based prescription medications available in the UK that may help alongside lifestyle changes. This guide explains your options, NHS eligibility criteria, and how to discuss weight loss medication with your GP to find the right approach for your health goals.
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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 Options
Three medications are currently licensed in the UK for weight management in adults: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). All work by activating GLP-1 or dual GIP/GLP-1 hormone pathways to reduce appetite and support feeling fuller after meals.
Mounjaro is a once-weekly injection with a dual mechanism, and clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks alongside reduced-calorie diet and increased physical activity. Wegovy is also once-weekly and demonstrated average weight loss of around 15% in clinical trials. Saxenda is a daily injection option.
All three are prescription-only medicines requiring a clinical assessment before being prescribed. Use our free GLP-1 weight loss calculator above to explore projected outcomes at different doses, and check your starting point with our BMI calculator to understand your personal health context.
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.
NHS Eligibility and How to Access Treatment
You may be eligible for prescription weight loss medication through the NHS if you have a BMI of 30 kg/m² or above, or 27–29.9 kg/m² with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, lower BMI thresholds apply.
Access through the NHS involves referral to a specialist tier 3 weight management service from your GP—waiting times and availability vary significantly by region. Alternatively, prescription weight loss medication is available privately through UK-licensed online prescribers following a clinical assessment, without requiring NHS referral. Your GP can help you determine eligibility and discuss which approach is right for you and your goals for sustainable weight management.
- 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.
What's the difference between weight loss camps and prescription medication?
Weight loss camps are residential programmes combining diet, exercise, and behavioural support. Prescription medications like Mounjaro and Wegovy work by reducing appetite and supporting sustainable lifestyle changes. Many people combine medication with lifestyle support for better long-term outcomes. Neither approach is one-size-fits-all—your GP can help you choose.
Am I eligible for weight loss medication on the NHS?
You may be eligible if your BMI is 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or high blood pressure. Lower thresholds apply for certain ethnic backgrounds. Ask your GP for an assessment of your eligibility and which treatment pathway suits your health needs.
How quickly will prescription weight loss medication work?
Results vary between individuals. Clinical trials showed average weight loss of 15–21% over 72 weeks with Mounjaro, and around 15% with Wegovy, alongside reduced-calorie diet and increased physical activity. Weight loss typically begins within weeks but continues over several months. Individual outcomes depend on many factors.
Can I access weight loss medication privately if the NHS waiting list is long?
Yes. Private prescription weight loss medication is available through UK-licensed online prescribers following a clinical assessment. This can be faster than NHS routes but involves costs typically ranging from £129–£320 per month depending on dose and provider. Your GP can still provide ongoing support.
What should I discuss with my GP about weight loss options?
Ask your GP about your personal eligibility for prescription medication, available NHS services in your area, waiting times, any health conditions that might affect suitability, potential side effects, and whether medication combined with lifestyle support is appropriate for your weight management goals and health context.
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.