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
Is Mounjaro Available On The NHS?
Yes, Mounjaro (tirzepatide) is available on the NHS in the UK, but access depends on where you live and which specialist weight management service covers your area. NICE has approved tirzepatide for use within NHS specialist tier 3 and tier 4 weight management services. However, NHS availability is limited, waiting lists can be very long, and not all areas offer equal access. Private prescription routes are also available if you'd prefer to avoid NHS waiting times.
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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 Availability And Eligibility
NHS access to Mounjaro is through specialist weight management services, not your GP. You cannot get a standard GP prescription for Mounjaro on the NHS — it must be initiated within a tier 3 or tier 4 specialist service.
To access Mounjaro through the NHS, you typically need:
- A BMI of 30 kg/m² or above, or BMI 27–29.9 with weight-related health conditions (type 2 diabetes, prediabetes, high blood pressure, sleep apnoea, or cardiovascular disease)
- For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds may apply (BMI 27.5 or above)
- A GP referral to your local specialist weight management service
- Clinical assessment confirming suitability for tirzepatide
Waiting times: Many NHS areas have waiting lists of 6–18 months or longer for specialist weight management services. Availability varies significantly by region — some integrated care boards (ICBs) offer Mounjaro more readily than others. Check with your GP about your local service and expected waiting time.
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.
Private Mounjaro Cost And Online Access In The UK
Private Mounjaro prescriptions are widely available through UK-licensed online prescribers without NHS referral. You pay for both the prescription consultation and the medication itself.
Typical private Mounjaro costs in the UK:
- Starting dose (2.5 mg): approximately £129–£180 per month
- Maintenance doses (5–15 mg): approximately £199–£320 per month depending on dose and provider
- Initial consultation fee: typically £40–£99 (some providers include this in the first prescription cost)
Cost varies between different private prescribing services — it's worth comparing. Most private services deliver within 2–5 working days. Our free GLP-1 weight loss calculator can help you estimate potential outcomes at different doses, which may inform your decision about whether prescription treatment is right for you.
- 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.
Do I need a GP referral to get Mounjaro on the NHS?
Yes. To access Mounjaro through NHS specialist weight management services, you need a referral from your GP. Your GP will refer you to your local tier 3 service, which then assesses whether Mounjaro is appropriate for you. Private routes do not require an NHS referral.
How long is the NHS waiting list for Mounjaro?
Waiting times vary significantly by region, typically 6–18 months or longer in many areas. Some ICBs have shorter waits; others have much longer delays. Ask your GP about your local specialist service's current waiting time when you request a referral.
Is Mounjaro cheaper on the NHS or through private prescription?
NHS prescription is free once approved, making it significantly cheaper than private routes. However, the trade-off is waiting time. Private Mounjaro costs £129–£320 per month depending on dose, but you can access it within days rather than months.
Can I start Mounjaro privately and then switch to NHS later?
This is possible in some cases, but you would need to discuss it with your GP and local specialist service. Switching between services can complicate dose titration, so always inform both your private prescriber and your GP if you're considering a switch.
What's the difference between NHS and private Mounjaro treatment?
The medication is identical. The main difference is waiting time (months on NHS vs days private), cost (free NHS vs £129–£320/month private), and the setting of clinical oversight. Both require prescription and clinical assessment.
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.