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 Do You Get Mounjaro in the UK?
Mounjaro (tirzepatide) is available in the UK through two main routes: NHS specialist weight management services and private prescription through GPhC-registered pharmacies. Access differs significantly depending on which pathway you choose, eligibility criteria, and your local NHS availability. This guide explains both options, what to expect from each, and how the NHS referral process works for this dual GIP and GLP-1 receptor agonist injection.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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 Access to Mounjaro — Eligibility and the Referral Pathway
NHS access to Mounjaro is through specialist tier 3 and tier 4 weight management services, not standard GP prescription. NICE has approved tirzepatide for use within these specialist services, but availability varies significantly across different NHS regions and integrated care boards (ICBs).
To access Mounjaro through the NHS:
- Your GP must refer you to a specialist weight management service in your area
- You'll be assessed by the specialist team to determine eligibility
- Eligibility criteria include BMI of 30 or above, or BMI of 27–29.9 with weight-related health conditions such as type 2 diabetes, hypertension, or sleep apnoea
- For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds may apply (27.5 and above)
- The specialist team will manage your dose titration, monitoring, and ongoing care
NHS waiting times for specialist weight management services can be substantial—many areas have waiting lists of several months to over a year. Availability also depends on your region; some ICBs may not currently offer tirzepatide.
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.
Private Prescription Route — Direct Access Without NHS Referral
Mounjaro is also available privately through GPhC-registered online pharmacies following a clinical assessment with a UK-licensed prescriber. This route does not require NHS referral and can be faster than waiting for specialist NHS services.
With private prescription, you'll complete an online health questionnaire and have a consultation with a registered prescriber who will assess whether Mounjaro is suitable for you. If approved, a prescription is issued and dispensed by the pharmacy. Costs typically range from £129–£320 per month depending on your dose (the starting Mounjaro KwikPen dose is 2.5 mg, with titration up to a maximum of 15 mg weekly). Use our free GLP-1 weight loss calculator to explore projected outcomes at different doses, and track your progress with 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.
Can I get Mounjaro on the NHS?
Yes, NICE has approved tirzepatide for use within NHS specialist tier 3 and tier 4 weight management services. Access is through specialist referral, not standard GP prescription. Availability varies by region and waiting times can be lengthy.
How do I get referred to an NHS specialist weight management service?
Ask your GP for a referral to the specialist weight management service in your area. Your GP will assess your eligibility and send your referral. You'll then be contacted by the specialist team to arrange an appointment and further assessment.
What if I don't want to wait for NHS services?
You can access Mounjaro privately through a GPhC-registered online pharmacy. This requires an online clinical assessment and prescription from a UK-licensed prescriber. It's faster but involves private costs.
How much does Mounjaro cost privately in the UK?
Private Mounjaro typically costs £129–£320 per month depending on your dose. The starting dose (2.5 mg) is usually cheaper than higher maintenance doses (10–15 mg). Prices vary between different private providers.
What's the difference between NHS and private Mounjaro?
The medication is identical. NHS access involves specialist referral and longer waiting times but is free. Private access is faster and doesn't require NHS referral but involves out-of-pocket costs. Both require clinical assessment before prescription.
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.