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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Mounjaro Cost in the UK — What You Need to Know
Mounjaro (tirzepatide) pricing in the UK varies depending on where you access it and which dose you're prescribed. Private prescription costs typically range from £129 to £320 per month depending on your starting dose and the provider. If you're wondering about price changes, it's important to understand how UK pricing works for this prescription-only weight management injection, and what your options are through both NHS and private routes.
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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 Costs and Pricing in the UK
Private prescription pricing for Mounjaro (tirzepatide) in the UK is set by individual online prescribing services and registered pharmacies — there is no fixed national price. Costs typically start at around £129–£160 per month for starting doses (2.5 mg to 5 mg) and increase to £220–£320 per month for higher maintenance doses (10 mg to 15 mg). Each Mounjaro KwikPen contains 4 weeks of doses, so monthly pricing represents a standard 4-week supply.
Pricing can fluctuate based on demand, supply chain factors, and individual provider costs. Some services offer discount codes or loyalty programmes, though these vary. It's worth comparing costs across different GPhC-registered online prescribing services, as prices are not standardised. The dose titration schedule means you'll start on a lower dose and escalate over several weeks — so your initial costs may be lower than the maximum dose price.
- Starting doses (2.5–5 mg): typically £129–£180/month
- Mid-range doses (7.5–10 mg): typically £180–£250/month
- Higher doses (12.5–15 mg): typically £250–£320/month
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 Access vs Private Prescription Route
NHS access to tirzepatide (Mounjaro) is available through NICE-approved specialist weight management services (tier 3 and 4). NHS prescription is free once prescribed, but access requires referral from your GP to a specialist service — availability varies significantly by region and waiting times can be substantial. Private access doesn't require NHS referral: you complete an online clinical assessment with a UK-licensed prescriber, and if approved, receive a prescription dispensed by a GPhC-registered pharmacy. This route is faster (often within days) but you pay privately for each supply. Consider your personal circumstances: NHS is free but may involve waiting months; private is immediate but ongoing cost. Our GLP-1 weight loss calculator can help you estimate potential outcomes across different doses.
Before committing to private Mounjaro, understand the full picture: treatment typically continues for at least 6–12 months for meaningful weight loss results, so budget accordingly. Prescription-only status means a prescriber must assess your eligibility — you cannot simply order Mounjaro without a clinical consultation. Factors affecting your eligibility include your BMI, any weight-related health conditions (like type 2 diabetes or hypertension), and medical history. Online consultations usually take 10–15 minutes and cost £0–£30. Always check whether your chosen provider offers dose adjustments and ongoing support — some charge consultation fees each time you escalate doses.
- 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 NHS free if prescribed on the NHS?
Yes — once prescribed through an NHS specialist weight management service, Mounjaro is free on the NHS like all prescription medicines. However, access requires GP referral to a tier 3 service and availability varies by region. Waiting lists can be long.
Can my GP prescribe Mounjaro privately?
Your GP can prescribe Mounjaro privately if they choose, but most GPs refer patients to online prescribing services instead. Private prescribing requires a clinical assessment and you pay the full cost privately.
What dose will I start on when prescribed Mounjaro?
You'll start on 2.5 mg once weekly for the first 4 weeks, then escalate gradually every 4 weeks by 2.5 mg increments up to your target dose. Most people maintain at 10 mg or 15 mg. Starting low minimises side effects.
Does Mounjaro cost change between suppliers in the UK?
Yes — prices vary between different GPhC-registered online services. It's worth comparing quotes across providers, as costs can differ by £50–£100+ per month at the same dose. Some offer discount codes.
How do I know if I'm eligible for Mounjaro on prescription?
You're typically eligible if you have a BMI of 30+ or 27+ with a weight-related health condition (type 2 diabetes, hypertension, sleep apnoea, etc.). An online prescriber will assess your eligibility during your consultation — they'll review your BMI using our free BMI calculator equivalent and medical history.
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.