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
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How Much Does Mounjaro Cost in the UK?
Mounjaro (tirzepatide) is available in the UK through both NHS specialist services and private online prescribing. The cost varies significantly depending on where you access it. On the NHS, Mounjaro is provided free through tier 3 weight management services, though availability and waiting times vary by region. Privately, prices typically range from £120 to £320 per month depending on your dose and the prescriber. Understanding these costs and access routes helps you make an informed decision about which option suits your circumstances.
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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.
Private Mounjaro Prescription Costs in the UK
Private prescription costs for Mounjaro depend on your dose and the prescriber you use. Starting doses (2.5 mg) typically cost around £120–£160 per month, while maintenance doses (10–15 mg) range from £200–£320 per month. Each KwikPen contains 4 weekly injections, so you'll need one pen per month. Costs may include the consultation fee (usually £40–£100), prescription fee, and dispensary costs combined. Some private prescribers offer package deals or subscription models that may reduce the overall cost. Price comparison across different GPhC-registered online prescribers can help you find the best value, though the cheapest option is not always the best—ensure any prescriber conducts a proper clinical assessment and that your prescription is issued by a UK-licensed doctor.
- Starting dose (2.5 mg): approximately £120–£160/month
- Mid-range dose (5–7.5 mg): approximately £150–£220/month
- Maximum dose (15 mg): approximately £280–£320/month
- Consultation fees: typically £40–£100 (one-off or recurring)
- Use our free GLP-1 weight loss calculator to estimate which dose might be appropriate for you
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 Access to Mounjaro in the UK
NHS access to Mounjaro is free on prescription but available only through specialist tier 3 weight management services. Your GP must refer you, and waiting lists can be months to over a year in many areas. NICE has approved tirzepatide for NHS use, but availability depends on your integrated care board (ICB) funding and local commissioning. Private access is faster—you can book an online consultation within days and receive a prescription if clinically appropriate—but you pay the full cost. The private route suits those who cannot wait for NHS assessment or whose local NHS service has no capacity. Your GP can advise on local NHS options, or you can explore GPhC-registered private prescribers for immediate access. Check your BMI using our free BMI calculator to confirm you meet the eligibility criteria (BMI 30+, or 27–29.9 with weight-related health conditions) before starting either route.
- 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.
Why does Mounjaro cost more at higher doses?
Mounjaro dosing starts at 2.5 mg and titrates weekly up to 15 mg maximum. You need one KwikPen (4 injections) per month, and higher-dose pens cost more to manufacture and supply. As you titrate from 5 mg to 15 mg, your monthly cost increases proportionally. Most people stabilise at a maintenance dose between 10–15 mg.
Can I get Mounjaro cheaper on the NHS?
Yes, Mounjaro is completely free on the NHS through specialist tier 3 weight management services. However, you must be referred by your GP and may face significant waiting lists (3–12 months in many areas). NICE recommends it for adults with BMI 30+ or BMI 27–29.9 with weight-related health conditions, but regional ICB funding varies.
What's the difference between Mounjaro and Wegovy costs in the UK?
Both are available privately at similar price ranges (£120–£320/month depending on dose). Mounjaro is a dual GIP/GLP-1 agonist while Wegovy (semaglutide) is GLP-1 only. Clinical trials suggest Mounjaro may produce slightly higher average weight loss (~21% vs ~15%), but individual results vary. Compare both with your prescriber to find the best fit for your needs and budget.
Are there hidden costs I should know about when buying Mounjaro privately?
Hidden costs may include the initial consultation (£40–£100), repeat consultation fees (often £20–£50 per refill), prescription fees, and dispensary margins. Some prescribers bundle these; others charge separately. Always ask for a full price breakdown before booking, including whether consultations are recurring fees or one-off. Budget for approximately £150–£350/month all-in for starting doses.
How do I know if a private Mounjaro prescriber is legitimate?
Check that the prescriber is registered with the MHRA and that their accompanying doctor is registered with the GMC (General Medical Council). Legitimate GPhC-registered pharmacies will conduct a thorough online clinical assessment, ask about your medical history, and issue a prescription from a UK-licensed doctor. Avoid prescribers who skip medical questions or offer unrealistically cheap prices—prescription tirzepatide cannot be sourced significantly below market cost from legitimate UK sources.
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.