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
GLP-1 Weight Loss Through the NHS
GLP-1 weight loss medications are available on the NHS, but access works differently from standard GP prescriptions. These medications—including semaglutide (Wegovy) and tirzepatide (Mounjaro)—are prescription-only and prescribed through specialist NHS weight management services, not in primary care. If you're interested in weight management support, your GP can refer you to tier 3 services in your area, though availability and waiting times vary significantly by region. This guide explains how NHS GLP-1 treatment works, who's eligible, and what to expect.
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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.
How NHS GLP-1 Weight Loss Access Works
GLP-1 medications for weight management sit within the NHS structured weight management pathway. Most referrals start with your GP, who assesses whether you meet eligibility criteria and have exhausted tier 1 and tier 2 support (self-help resources and group-based programmes). If appropriate, your GP refers you to your local NHS Integrated Care Board (ICB) specialist weight management service (tier 3). These multidisciplinary teams—comprising doctors, nurses, psychologists, and dietitians—conduct comprehensive assessments before prescribing.
Key facts about NHS GLP-1 access:
- Prescription-only—requires clinical assessment and ongoing monitoring
- Available through tier 3 specialist services only—not standard GP prescription
- Prescribing varies by region; some ICBs have formal tirzepatide or semaglutide pathways, others don't
- Often involves waiting lists of several months to over a year in many areas
- Requires commitment to lifestyle changes (diet and physical activity) alongside medication
- Ongoing monitoring appointments typically required during treatment
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 What to Expect
You may be eligible for GLP-1 weight loss medication through the NHS if you have a BMI of 30 or above (or 27+ with weight-related health conditions such as type 2 diabetes, hypertension, or sleep apnoea). People of South Asian, Chinese, Black African, or Black Caribbean heritage may qualify at lower BMI thresholds due to higher health risks at these levels. Check your BMI using our free BMI calculator to see where you stand. Once referred to specialist services, expect a full health assessment, discussion of lifestyle support, and clear information about how the medication works, potential side effects, and realistic weight loss expectations. Weight loss typically ranges from 14–21% of body weight over 12–18 months, though individual results vary. Use our free GLP-1 weight loss calculator to explore potential outcomes at different doses.
NHS vs private options: Many people choose private online prescribing because NHS waiting times are lengthy in their area. Private prescribing follows a similar clinical assessment process but occurs faster and outside the NHS system. Both NHS and private routes require an actual prescription from a UK-licensed prescriber and ongoing clinical monitoring. Neither option assures weight loss—results depend on adherence to medication, dietary changes, and increased physical activity. Your GP can advise whether specialist NHS referral or exploring private options makes sense for your situation.
- 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 my GP prescribe GLP-1 weight loss medication directly?
No. In the UK, GLP-1 medications for weight management are only prescribed through specialist tier 3 NHS weight management services, not in primary care. Your GP can refer you to these services if you meet eligibility criteria, but the prescription itself comes from the specialist team after comprehensive assessment.
How long does it take to access GLP-1 treatment on the NHS?
Waiting times vary significantly by region. Some specialist services have waits of 3–6 months; others exceed 12 months or longer. This variation depends on local ICB capacity, funding, and demand. Ask your GP about current waiting times in your area when discussing referral.
What's the difference between Wegovy and Ozempic for weight loss?
Both contain semaglutide, but Wegovy is licensed specifically for weight management, whereas Ozempic is licensed for type 2 diabetes. Using Ozempic for weight loss is off-label in the UK. Wegovy is the appropriate licensed choice for weight management—though both require prescription and clinical assessment before use.
If I can't access GLP-1 on the NHS quickly, what are my other options?
Some people pursue private online prescribing through registered UK healthcare providers while waiting for NHS assessment. This requires a clinical consultation with a licensed UK prescriber and costs between £129–£320+ monthly depending on dose. Both NHS and private routes require genuine clinical assessment—avoid unregulated sources.
Will the NHS weight management service support me beyond just prescribing medication?
Yes. Tier 3 specialist services provide multidisciplinary support including dietitian guidance, behaviour change coaching, and medical monitoring. GLP-1 medications are used alongside structured lifestyle interventions—not instead of them. This comprehensive approach significantly improves outcomes compared to medication alone.
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.