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 available in the UK through both NHS specialist services and private prescribing, with costs varying significantly depending on which route you choose. Understanding the true cost of Mounjaro—including prescription fees, dose titration, and ongoing expenses—helps you make an informed decision about whether this weight loss injection is right for your situation and budget.
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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 Costs: Private Prescription Pricing in the UK
Private prescription costs for Mounjaro in the UK typically range from £129 to £320 per month, depending on the dose you're prescribed. Starting doses (2.5 mg and 5 mg) are usually at the lower end, while higher maintenance doses (15 mg) cost more. Each KwikPen contains 4 weeks of doses, so you're buying a month's supply at a time. It's important to note that prices vary between different GPhC-registered online prescribing services, so comparing options is worthwhile. Some providers bundle consultations with prescriptions, whilst others charge separately for the clinical assessment—typically £20 to £50. Unlike NHS prescriptions, private Mounjaro is not subject to the standard UK prescription charge, so you pay the full pharmacy price. As you progress through dose titration (typically taking 16–20 weeks to reach maximum dose), your monthly cost will gradually increase as your dose increases. Budget accordingly if you're planning longer-term treatment.
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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 Routes and Timelines
NHS access to Mounjaro is free at point of use but requires referral to a tier 3 specialist weight management service—typically through your GP. NHS NICE guidance approves tirzepatide for weight management in eligible adults, but availability varies significantly by region. Waiting lists for NHS specialist services can range from several months to over a year in some areas. Private prescription is faster—you can typically get an appointment and prescription within days—but you pay the full cost upfront. Use our free GLP-1 weight loss calculator to estimate potential weight loss at different doses, which may help you decide if the investment is worthwhile for your situation. The choice between NHS and private depends on your budget, timeline, and whether you meet NHS eligibility criteria.
- 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 cheapest way to get Mounjaro in the UK?
Through the NHS, Mounjaro is completely free after referral to a specialist service—but waiting lists can be lengthy. Private prescription costs £129–£320 per month depending on dose, but is faster to access. Compare both options based on your timeline and budget before deciding.
Do I need a prescription to buy Mounjaro in the UK?
Yes, Mounjaro is a prescription-only medicine in the UK. You cannot buy it over-the-counter. You'll need a prescription from either an NHS specialist service or a UK-licensed private prescriber following a clinical assessment.
How long does the starting dose last, and what does it cost?
The starting 2.5 mg KwikPen contains 4 weeks of injections (one dose per week), typically costing £129–£150 privately. You'll remain on this dose for 4 weeks before escalating, so expect to purchase a new pen every month during titration.
Are there any ways to reduce the cost of private Mounjaro?
Some private prescribing services offer package deals combining consultation and prescription, or discounts for paying upfront for multiple months. Compare different GPhC-registered providers—prices do vary. NHS access remains the most cost-effective option if you can wait for a specialist appointment.
Will private Mounjaro cost less than a private GP consultation elsewhere?
Private Mounjaro through online prescribing services (£129–£320 monthly) is typically more affordable than traditional private weight management clinics, which may charge £300–£500+ per appointment without supplying medication. The price reflects the full cost of the injection itself, not just the consultation.
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.