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 Does Mounjaro Cost in the UK?
Mounjaro (tirzepatide) is a prescription-only weight management injection available in the UK at doses ranging from 2.5 mg to 15 mg per week. The cost depends on whether you access it through the NHS or privately. NHS access is typically free at the point of care but involves waiting lists and specialist referral, while private prescriptions cost between £150 and £300 monthly depending on dose. Understanding your eligibility and the available doses can help you make an informed decision about this treatment option.
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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.
Mounjaro Doses and NHS Eligibility in the UK
Mounjaro dose schedule: Treatment starts at 2.5 mg once weekly for 4 weeks, then escalates every 4 weeks: 5 mg, 7.5 mg, 10 mg, 12.5 mg, and finally 15 mg (maximum). Each KwikPen contains 4 weekly doses. Your prescriber adjusts your dose based on your response and tolerability.
NHS eligibility for Mounjaro: You may be eligible through NHS specialist weight management services (tier 3) if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions including type 2 diabetes, hypertension, or cardiovascular disease. South Asian, Chinese, Black African, and Black Caribbean adults may qualify at lower BMI thresholds (27.5 or above). NICE has approved tirzepatide for NHS use, though regional availability varies significantly and waiting lists can be lengthy.
Use our free BMI calculator above to check if you might meet initial eligibility criteria for specialist assessment.
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.
Mounjaro Cost: NHS vs Private Routes in the UK
NHS route: Once prescribed through a tier 3 weight management service, Mounjaro is typically free on the NHS (except standard prescription charges if applicable). However, access involves GP referral, specialist assessment, and can involve months-long waiting lists depending on your local ICB.
Private route: Costs range from approximately £150–£300 per month depending on your dose level. Mounjaro vs Wegovy pricing is comparable—both are available through GPhC-registered online pharmacies following an online clinical assessment. Private access is immediate but requires meeting clinical eligibility criteria assessed by a licensed prescriber.
Track your weight loss progress with our free progress tracker once you begin treatment.
- 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's the difference between Mounjaro doses?
Mounjaro starts at 2.5 mg and escalates weekly doses over 5 months to reach 15 mg maximum. Each dose level is maintained for 4 weeks to assess tolerance before increasing. Higher doses typically produce greater average weight loss in clinical trials, though individual response varies.
Is Mounjaro available on the NHS in the UK?
Yes, NICE has approved tirzepatide (Mounjaro) for NHS use through specialist tier 3 weight management services. You'll need a GP referral and specialist assessment. Availability varies by region and waiting lists can be significant. Private access is faster but involves clinical assessment fees.
How much weight loss can I expect with Mounjaro?
Clinical trials (SURMOUNT-1) showed average weight loss of 15–21% of body weight at 15 mg dose over 72 weeks alongside lifestyle changes. Individual results vary significantly. Use our GLP-1 weight loss calculator to estimate potential outcomes based on your starting weight and dose.
How do Mounjaro costs compare to Wegovy on the NHS?
Both are prescription-only. NHS access is free once prescribed but involves specialist referral and varies by region. Privately, both cost roughly £150–£300 monthly depending on dose. Mounjaro and Wegovy have similar efficacy but different mechanisms—Mounjaro is a dual GIP/GLP-1 agonist while Wegovy is GLP-1 only.
What happens if I can't afford private Mounjaro?
Request a GP referral to your local NHS weight management service. Though waiting lists exist, this remains your access to free treatment. Some areas have newer capacity than others. Ask your GP about tier 2 community support programmes while awaiting specialist 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.