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 Generic — Understanding Cost and Access in the UK
Mounjaro (tirzepatide) is not currently available as a generic medication in the UK — it remains a branded, prescription-only medicine manufactured by Eli Lilly. Whether you access Mounjaro through the NHS or privately, cost and availability depend on your eligibility and the route you choose. This guide explains how to access Mounjaro in the UK, what you can expect to pay, and how the NHS and private routes differ.
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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.
Cost and Access Routes in the UK
Mounjaro is available through two main routes in the UK:
- NHS specialist weight management services: If prescribed through an NHS tier 3 or 4 specialist service following referral from your GP, there is no direct cost — you pay only your standard prescription charge (currently £9.65 per item in England, or free if eligible). However, NHS access varies significantly by region and availability can be limited, with waiting lists often extending many months.
- Private prescription: Through GPhC-registered online pharmacies and private prescribers, Mounjaro costs typically range from £129 to £320+ per month depending on the dose. A starting dose (2.5 mg) is usually cheaper than higher maintenance doses (10–15 mg). Private access does not require NHS referral but requires an online clinical assessment.
As tirzepatide remains under patent protection, a generic version is unlikely to become available in the UK for several more years. When generics do eventually become available, prices are expected to decrease significantly — similar to what happened with earlier GLP-1 medications.
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 — Which Route Is Right for You?
NHS route: Eligible adults with a BMI of 30 or above (or 27–29.9 with weight-related health conditions) can ask their GP for referral to a specialist weight management service. Assessment is free, but you may wait months for an appointment. If prescribed, you'll receive Mounjaro at NHS cost. Use our free BMI calculator to check whether you might meet NHS eligibility criteria.
Private route: You can access Mounjaro privately without NHS referral. Complete an online consultation with a UK-licensed prescriber, who will assess your eligibility based on health history and measurements. If approved, a prescription is issued to a GPhC-registered pharmacy. The entire process typically takes 1–2 weeks. Try our GLP-1 weight loss calculator to explore potential results and see if Mounjaro might suit your weight loss goals.
- 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 there a generic Mounjaro available in the UK yet?
No. Mounjaro (tirzepatide) remains a branded, patent-protected medication. It is not available as a generic in the UK. Eli Lilly holds the exclusive rights to tirzepatide manufacturing. When the patent expires (expected in the early 2030s), generics may become available at lower cost.
How much does Mounjaro cost on the NHS?
If prescribed through an NHS specialist service, Mounjaro costs only the standard prescription charge (£9.65 per item in England, or free if you qualify for free prescriptions). However, NHS availability is limited and regional, with significant waiting lists in many areas.
How much does Mounjaro cost privately in the UK?
Private Mounjaro typically costs £129–£320+ per month depending on the dose. A 2.5 mg starting dose is usually cheaper (around £129–£180/month), while 10 mg and 15 mg maintenance doses cost more (£220–£320+/month). Prices vary between different private prescribing services.
Can I switch from Mounjaro to a generic weight loss injection?
Currently, there is no generic tirzepatide. If you need a more affordable GLP-1 option, you could discuss switching to Wegovy (semaglutide) with your prescriber — though Wegovy is also brand-name and requires prescription. When tirzepatide generics eventually launch, your prescriber can help you transition.
What is the private prescription process for Mounjaro in the UK?
Complete an online health questionnaire with a UK-licensed prescriber. If you meet eligibility criteria (BMI ≥30 or ≥27 with health conditions), a prescription is issued. Present it to a GPhC-registered pharmacy, who dispense Mounjaro. The entire process takes 1–2 weeks. You'll need to attend follow-up consultations to monitor progress and adjust doses.
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.