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
Can I Get Mounjaro On The NHS?
Yes, Mounjaro (tirzepatide) is available on the NHS for eligible adults, but access is limited and varies significantly by region. NICE has approved tirzepatide for use within NHS specialist weight management services, though getting a prescription typically requires referral to a tier 3 or tier 4 specialist service rather than through your standard GP. Waiting times can be substantial in many areas. Many people in the UK access Mounjaro through private online prescribing services as an alternative to NHS waiting lists.
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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.
NHS Access To Mounjaro — What You Need To Know
Mounjaro is licensed for NHS use, but only through specialist tier 3 and tier 4 weight management services, not in general practice. To access Mounjaro via the NHS, you typically need to be referred by your GP to your local integrated care board (ICB) specialist weight management service. These services exist in all NHS regions, but availability and waiting times vary dramatically — some areas have waits of 6–12 months or longer.
NHS eligibility criteria require a BMI of 30 kg/m² or above, or a BMI of 27–29.9 kg/m² with at least one weight-related health condition (type 2 diabetes, prediabetes, hypertension, sleep apnoea, or cardiovascular disease). South Asian, Chinese, Black African, or Black Caribbean adults may qualify at lower BMI thresholds — your GP can advise. Once referred, the specialist service will assess you comprehensively before deciding whether tirzepatide is suitable. Weight loss medications like Mounjaro are prescribed alongside a reduced-calorie diet and increased physical activity.
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 Mounjaro — Understanding Your Options
Many people struggle with NHS waiting times for Mounjaro and turn to private online prescribing instead. Private access requires an online consultation with a UK-licensed prescriber who will assess your medical history and suitability. If approved, a prescription is issued and dispensed by a GPhC-registered pharmacy — without requiring a GP referral or NHS specialist service. Private Mounjaro costs typically range from £150–£320 per month depending on your dose and provider.
Calculate your potential weight loss with our GLP-1 weight loss calculator to understand possible outcomes with tirzepatide. Both NHS and private routes provide the same medication; the main differences are waiting times, cost, and how the assessment is conducted. Your decision may depend on your ability to wait, your budget, and your preference for NHS or private care.
- 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 NICE's position on Mounjaro and the NHS?
NICE approved tirzepatide (Mounjaro) for use within NHS specialist weight management services. However, approval at NICE level does not mean automatic prescription in general practice — access is limited to tier 3 and tier 4 specialist services with significant regional variation in availability and waiting times.
How long is the NHS waiting list for Mounjaro?
Waiting times vary considerably by region. Some areas may assess you within 3–6 months, while others have waiting lists of 12 months or longer. Contact your local ICB specialist weight management service for your specific waiting time, or ask your GP during referral.
Can my GP prescribe Mounjaro directly?
In most cases, no. Your GP cannot prescribe Mounjaro in general practice — it must be initiated by a specialist weight management service following referral. Your GP can refer you, but the specialist service makes the prescription decision after a comprehensive assessment.
What's the difference between NHS Mounjaro and private Mounjaro?
The medication is identical. The difference is in how you access it: NHS requires referral and specialist assessment but is free; private requires an online consultation, a private prescription, and costs £150–£320 monthly. Both require clinical assessment before prescription.
Am I eligible for NHS Mounjaro?
You may be eligible if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions (diabetes, prediabetes, hypertension, sleep apnoea, or cardiovascular disease). South Asian, Chinese, Black African, or Black Caribbean adults may have lower thresholds. Your GP can assess your eligibility and make a referral to your local specialist service.
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.