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
How Much Is Mounjaro On The NHS?
Mounjaro (tirzepatide) is free when prescribed through the NHS, but availability varies significantly across the UK. Access is not through standard GP prescription — instead, it's provided through specialist tier 3 weight management services following NICE approval. However, waiting lists for these services can be lengthy in many regions, and eligibility criteria are strict. Many people choose to access Mounjaro privately instead due to faster availability.
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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 Mounjaro Access: Eligibility And NICE Guidance
Mounjaro on the NHS is free at the point of use, but only through specialist weight management services (tier 3), not from your GP. NICE approved tirzepatide for NHS use in 2024, but regional availability remains limited.
You may be eligible if you:
- Have a BMI of 30 kg/m² or above, or BMI 27–29.9 with weight-related health conditions (type 2 diabetes, high blood pressure, sleep apnoea, cardiovascular disease)
- Have tried lifestyle changes without sufficient weight loss
- Are referred to specialist services by your GP
- Meet your local Integrated Care Board (ICB) criteria — these vary by region
For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds (27.5+) typically apply due to higher health risks at lower weights. Unlike Ozempic (which is for diabetes), Mounjaro's NHS approval is specifically for weight management.
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 Waiting Lists vs Private Access
The main challenge with NHS Mounjaro is waiting time. Specialist weight management services in many areas have waiting lists of 6–18 months or longer. During this time, you'll typically be offered diet and lifestyle support but not medication.
Private route alternative: Many people access Mounjaro privately through GPhC-registered online prescribing services following a clinical assessment. Private costs range from £150–£320 per month depending on dose, offering faster access without NHS waiting lists. Both routes require a UK-licensed prescriber to assess your suitability. Your GP can advise on NHS availability in your area and help you understand your options.
- 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.
Is Mounjaro free on the NHS?
Yes, Mounjaro is free on the NHS when prescribed through specialist weight management services. However, availability varies by region and waiting lists can be 6–18+ months. Not all areas currently have Mounjaro available, even after NICE approval. Check with your local ICB or ask your GP about access in your area.
How do I access Mounjaro through the NHS?
Ask your GP for a referral to your local tier 3 specialist weight management service. They will assess your eligibility against NICE criteria, conduct a clinical review, and potentially prescribe Mounjaro if appropriate. You cannot get Mounjaro directly from your GP — it must come through specialist services.
What's the difference between NHS and private Mounjaro?
NHS Mounjaro is free but involves waiting lists and regional availability limitations. Private Mounjaro is available faster (within days) through online prescribing services but costs £150–£320/month depending on dose. Both require a UK-licensed prescriber assessment. The medication itself is identical.
Can I switch from private Mounjaro to NHS?
You can request a GP referral to specialist services at any time. If accepted onto the NHS pathway, you may be able to continue Mounjaro through the NHS. However, NHS teams may require you to restart the dose titration schedule from 2.5mg rather than continuing at your private dose.
What if my area doesn't have NHS Mounjaro?
Contact your local ICB or ask your GP whether Mounjaro is available in your region. If not, you can explore private prescribing, ask about alternative GLP-1 medications like Saxenda on the NHS, or inquire about expected rollout timelines. Your GP can discuss all options with you.
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.