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
Where to Get Mounjaro Cheap in the UK
Mounjaro (tirzepatide) is a prescription-only weight management injection available through both NHS specialist services and private online prescribing in the UK. Cost varies significantly depending on where you access it — NHS availability is free but involves referral and waiting lists, whilst private options range from around £129 to £320+ per month depending on dose. Understanding your options helps you find affordable access to this medication whilst ensuring you receive proper clinical assessment.
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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 vs Private Access — Cost and Availability
NHS Access: If you qualify, Mounjaro prescribed through NHS specialist tier 3 weight management services is free at the point of use. However, access is limited — you must be referred by your GP to a specialist service in your area, and waiting lists can extend several months or longer depending on your region. Not all ICBs (Integrated Care Boards) fund tirzepatide equally, so availability varies significantly across the UK.
Private Access: Available through GPhC-registered online pharmacies following a clinical assessment with a UK-licensed prescriber. Private prescribing doesn't require NHS referral and typically offers faster access. Costs depend on dose — lower starting doses (2.5 mg, 5 mg) are cheaper than maintenance doses (10 mg, 15 mg). Many private providers offer tirzepatide at lower costs than brand-name Mounjaro by dispensing generic equivalents. Always check the prescriber is UK-licensed and the pharmacy GPhC-registered before proceeding.
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.
How to Find Affordable Mounjaro Treatment
To reduce costs, start by checking NHS eligibility — if you have a BMI of 30 or above, or 27 with weight-related health conditions (type 2 diabetes, hypertension, sleep apnoea), ask your GP for a referral to specialist services. Use our free BMI calculator above to check your eligibility. If NHS waiting times are too long, compare private prescribing services — prices and service quality vary. Generic tirzepatide (the active ingredient in Mounjaro) is often cheaper than branded Mounjaro KwikPens. Always verify the prescriber conducts a proper clinical assessment — cheap isn't valuable if the service skips safety checks. Track your progress using our free progress tracker once you start 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.
Is Mounjaro available on the NHS in the UK?
Yes, Mounjaro (tirzepatide) is approved for NHS use through specialist tier 3 weight management services. You must be referred by your GP and meet eligibility criteria (BMI 30+, or 27+ with weight-related health conditions). NHS availability and waiting times vary significantly by region — some areas have shorter waits, others much longer.
How much does Mounjaro cost privately in the UK?
Private Mounjaro costs typically range from £129 to £320+ per month depending on dose and provider. Lower starting doses (2.5 mg, 5 mg) are cheaper; higher maintenance doses (10 mg, 15 mg) cost more. Generic tirzepatide is often less expensive than brand-name Mounjaro KwikPens — compare providers for the best rate.
What's the difference between Mounjaro and Wegovy?
Both are prescription-only weight management injections available in the UK. Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist; Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials showed Mounjaro achieved slightly higher average weight loss (~15–21% vs ~15% body weight). Costs and availability differ — compare both options with your prescriber.
Do I need a prescription to buy Mounjaro in the UK?
Yes, Mounjaro is prescription-only. You cannot buy it without a valid UK prescription from a licensed prescriber. NHS prescriptions are free at dispensing; private prescriptions cost based on the pharmacy and dose. Always ensure your prescriber is UK-licensed and conducts a full clinical assessment before issuing a prescription.
Can I use a generic tirzepatide instead of branded Mounjaro to save money?
Generic tirzepatide contains the same active ingredient as Mounjaro (the KwikPen brand). Many private providers dispense generic equivalents at lower cost. Both are equally effective — the difference is brand name vs generic. Discuss generic options with your prescriber; many consider them suitable and more affordable alternatives.
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.