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 Training Programme: UK Prescription Medication Options
A comprehensive weight loss training programme often combines exercise, nutrition, and lifestyle changes. For eligible adults in the UK, prescription weight management medication can support these efforts alongside your training routine. This guide explains the prescription options available through the NHS and privately, who qualifies, and how to explore whether medication might help your weight management uk journey. Check your eligibility and use our free BMI calculator to understand your starting point.
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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 weight loss injections are currently licensed in the UK to support weight management alongside lifestyle changes:
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 receptor agonist, given as a once-weekly injection at doses from 2.5 mg to 15 mg. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks alongside reduced-calorie diet and increased activity.
- Wegovy (semaglutide) — a GLP-1 receptor agonist, given as a once-weekly injection at doses up to 2.4 mg. Evidence suggests average weight loss of around 15% of body weight in clinical trials.
- Saxenda (liraglutide) — a GLP-1 receptor agonist given as a once-daily injection at doses up to 3 mg. These medications work by helping regulate appetite and supporting feeling fuller after smaller meals.
Individual results vary significantly, and medications work best when combined with your training programme, reduced-calorie nutrition, and sustained physical activity. Try our GLP-1 weight loss calculator to see projected 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.
NHS Access vs Private Prescribing in the UK
NHS access: Weight loss medication is available through specialist tier 3 weight management services via referral from your GP. However, NHS availability varies significantly by region, and waiting lists can be lengthy in many areas. Private access: You can obtain a prescription through a UK-licensed online prescriber following a clinical assessment, without NHS referral. Your GP can advise on eligibility and whether prescription weight loss fits your training programme goals. Both routes require assessment to confirm you meet clinical criteria — typically a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or hypertension. Use our BMI calculator to check where you stand, then discuss options with your healthcare provider.
- 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 is a weight loss training programme?
A weight loss training programme combines structured exercise, nutrition guidance, and lifestyle changes to support healthy weight reduction. In the UK, NHS programmes like the weight loss injections nhs pathway work best alongside regular physical activity. Prescription medication can support your programme but is not a replacement for training and diet changes.
Am I eligible for prescription weight loss medication in the UK?
You may be eligible if you have a BMI of 30 or above, or 27–29.9 with weight-related conditions (type 2 diabetes, high blood pressure, sleep apnoea, or cardiovascular disease). Lower BMI thresholds apply if you are of South Asian, Chinese, Black African, or Caribbean heritage. Your GP or a licensed prescriber can assess your individual eligibility.
How much weight can I expect to lose with prescription medication?
Clinical trials show average weight loss of 15–21% of body weight, but individual results vary considerably. Weight loss depends on the medication, dose, your starting weight, adherence, diet, and exercise level. Faster or slower results are both normal. Track your progress with our free progress tracker.
Can I use weight loss medication while training?
Yes, prescription weight loss medications are designed to work alongside exercise and nutrition. In fact, combining medication with your training programme, reduced calories, and physical activity typically produces the best results. Always inform your prescriber about your training intensity so they can monitor your progress appropriately.
How do I start exploring weight loss medication?
Book an appointment with your GP to discuss whether you meet NHS criteria and could be referred to specialist services. Alternatively, you can access private online prescribing through UK-licensed healthcare providers. Both routes involve a clinical assessment. Use our free BMI calculator and weight loss calculator first to understand your starting point and estimated potential outcomes.
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.