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
Free tracker included with every download this week
NHS Fat Loss Pills — What Are Your Weight Management Options?
The NHS does prescribe weight loss pills and injections, though access varies significantly across the country. Prescription weight management medications like Wegovy (semaglutide) and Mounjaro (tirzepatide) are available through NHS specialist services for eligible adults. These are prescription-only medicines that work alongside lifestyle changes to help manage excess weight. Understanding your options through the NHS, and how to access them, starts with knowing your baseline health metrics and eligibility criteria.
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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.
What Fat Loss Pills Are Available on the NHS?
The NHS prescribes several weight management medications, primarily through tier 3 specialist weight management services. The main prescription options include Wegovy (semaglutide), a once-weekly GLP-1 receptor agonist injection, and Mounjaro (tirzepatide), a once-weekly dual GIP/GLP-1 injection. Both are licensed for weight management in UK adults and work by helping regulate appetite and food cravings. Additionally, Saxenda (liraglutide) is available, though it requires daily injections rather than weekly ones. These are not traditional "pills" but injectable medications prescribed following clinical assessment. Access through NHS specialist services typically involves referral from your GP, though waiting times vary considerably by region and ICB (integrated care board). Private prescribing through UK-licensed online services offers faster access but involves out-of-pocket costs.
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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.
Who Is Eligible for NHS Weight Loss Medication?
The NHS prescribes weight management medication for adults with a BMI of 30 or above, or BMI of 27–29.9 with a weight-related health condition. Qualifying conditions include type 2 diabetes, prediabetes, high blood pressure, abnormal blood fats, sleep apnoea, or cardiovascular disease history. For people of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recognises lower BMI thresholds due to higher health risks at lower weights. Check your BMI using our free BMI calculator above to see where you stand, and use our weight converter to switch between measurements if needed. Your GP can assess whether you meet eligibility criteria and discuss referral to specialist services. Individual circumstances matter — assessment happens on a case-by-case basis.
- 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.
Can I get weight loss pills on the NHS?
Yes. Weight loss medications like Wegovy and Mounjaro are available through NHS specialist tier 3 weight management services for eligible adults. You need referral from your GP and meet BMI and health criteria. Access varies by region, and waiting lists can be lengthy in some areas.
How do I access NHS fat loss medication?
Speak to your GP about referral to your local NHS tier 3 weight management service. They'll assess your eligibility based on BMI, health conditions, and medical history. Alternatively, private UK-licensed prescribers offer faster access without NHS referral, though this involves private cost.
How much weight can NHS weight loss pills help me lose?
Clinical trials show Wegovy helps average weight loss of around 15% of body weight, and Mounjaro around 15–21%. Individual results vary significantly. These medications work best alongside reduced-calorie diet and increased physical activity — they're not standalone solutions.
Are NHS weight loss pills the same as Ozempic?
No. Ozempic (semaglutide up to 2mg) is approved for type 2 diabetes. Wegovy (semaglutide 2.4mg) is the licensed weight management version. Using Ozempic for weight loss is off-label and not standard NHS practice for weight management.
What's the difference between NHS and private weight loss medication access?
NHS access is free but requires specialist referral and often involves waiting lists. Private access is faster but costs £129–£320 monthly. Both require prescription from UK-licensed prescribers and clinical assessment. Your GP can discuss which route suits your circumstances.
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.