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
Thigh Weight Loss: UK Prescription Medication Options
Losing weight from specific areas like the thighs is challenging because your body decides where fat is lost during weight loss. However, prescription weight management medication available in the UK may support overall weight loss, which can help reduce thigh fat over time. We explain your options for prescription weight loss medication, NHS eligibility criteria, and how to start a conversation with your GP about whether medication might be right for you.
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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 Weight Loss Medications Available
Three prescription-only medications are currently licensed in the UK for weight management in adults: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). These are GLP-1 receptor agonist medications (Mounjaro is a dual GIP/GLP-1 agonist) that work by helping regulate appetite and supporting you to feel fuller after smaller meals. In clinical trials, participants achieved average weight loss of 15–21% of their body weight over 52–68 weeks when using these medications alongside a reduced-calorie diet and increased physical activity. Individual results vary significantly. These are prescription-only medicines requiring a clinical assessment before being prescribed. Access in the UK is available through NHS specialist weight management services or private online prescribing following an assessment by a UK-licensed prescriber. Calculate your potential weight loss at different doses using our free GLP-1 weight loss calculator.
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 vs Private Access: How to Get Started
If you have a BMI of 30 or above (or 27 or above with weight-related health conditions like type 2 diabetes or high blood pressure), you may be eligible for prescription weight loss medication through the NHS. This requires referral to a tier 3 specialist weight management service — ask your GP about local services, though waiting lists can be lengthy in many areas. Private access is available immediately through online consultations with UK-licensed prescribers; if clinically appropriate, a prescription is issued and dispensed by a GPhC-registered pharmacy. Whichever route you choose, your prescriber will discuss whether this weight management approach is suitable for your personal health and goals. Track your progress using our free progress tracker once you begin your weight loss journey.
- 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 weight loss medication help me lose fat specifically from my thighs?
Weight loss medication supports overall body weight reduction, but you cannot target fat loss from specific areas like thighs. Your body naturally decides where fat is mobilised during weight loss. However, when you lose overall weight, you will lose fat from your thighs as part of that process. Clinical trials of GLP-1 medications showed average weight loss of 15–21% over 52–68 weeks, though individual results vary.
How do I know if I'm eligible for prescription weight loss medication in the UK?
You may be eligible if you have a BMI of 30 or above, or a BMI of 27–29.9 with weight-related health conditions (type 2 diabetes, high blood pressure, cardiovascular disease, sleep apnoea). Use our free BMI calculator to check your BMI. Your GP can assess your eligibility and refer you to specialist services, or you can pursue private assessment through an online consultation with a UK-licensed prescriber.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are prescription-only injections given once weekly. Mounjaro (tirzepatide) activates two hormone pathways (GIP and GLP-1) and may produce slightly higher average weight loss (15–21%). Wegovy (semaglutide) activates the GLP-1 pathway alone and achieved average weight loss of approximately 15% in trials. Both require clinical assessment. Your prescriber will discuss which is more appropriate for you based on your health profile.
How long does it take to see weight loss results from prescription medication?
Most people begin seeing changes within the first 4–6 weeks of treatment, though individual timelines vary. Clinical trials measured weight loss over 52–68 weeks, so patience and consistency are important. Results improve when medication is combined with a reduced-calorie diet and increased physical activity. Your progress tracker can help you record weekly changes and stay motivated throughout your journey.
Are prescription weight loss medications available on the NHS, or only privately?
Both options are available in the UK. NHS access is through tier 3 specialist weight management services following GP referral — availability and waiting times vary significantly by region. Private access is available through online consultations with UK-licensed prescribers without needing NHS referral. Costs differ between routes. Speak with your GP about local NHS options, or research private prescribing services if you prefer immediate access.
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.