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 Can I Get Mounjaro in the UK?
Mounjaro (tirzepatide) is a prescription-only weight loss injection available in the UK through two main routes: NHS specialist weight management services and private online prescribing. Access depends on your eligibility, BMI, and whether you meet specific health criteria. This guide explains both pathways, what to expect, and how to get started with this dual GIP and GLP-1 receptor agonist medication.
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
Getting Mounjaro through the NHS: You'll need a referral from your GP to a specialist tier 3 or tier 4 weight management service. Your GP will assess whether you meet eligibility criteria — typically a BMI of 30 or above, or 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea.
- Referral is made through your local integrated care board (ICB)
- Waiting times vary significantly by region — some areas have lists of 6–12 months or longer
- Once assessed by the specialist service, they'll discuss whether Mounjaro is appropriate for you
- If prescribed, the NHS covers the cost completely
- You'll receive ongoing support and monitoring through the service
NHS availability is patchy across the country. Check with your local ICB to see if Mounjaro is currently being prescribed in your area, as funding and availability differ by region.
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 Access to Mounjaro
Private prescribing route: You can access Mounjaro privately through GPhC-registered online pharmacies without needing an NHS referral. An online consultation with a UK-licensed prescriber assesses your eligibility based on BMI, health history, and weight-related conditions.
- No waiting list — prescriptions issued within days if you're eligible
- Cost ranges from approximately £120–£300 per month depending on dose
- You self-manage your treatment (though support is typically available)
- Prescriptions are dispensed by regulated pharmacies
Private access is faster than NHS but requires you to pay. Check that any provider is properly regulated — look for GPhC registration on their website. Use our free BMI calculator above to check your BMI before applying.
- 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.
Do I need a prescription for Mounjaro in the UK?
Yes, Mounjaro is prescription-only in the UK. You cannot buy it without a valid prescription from a UK-licensed prescriber. Both NHS and private routes require a clinical assessment to confirm you're eligible and that the medication is safe for you.
How long does it take to get Mounjaro on the NHS?
Waiting times depend on your region. Some areas have waiting lists of 6–12 months or longer for specialist weight management services. Private access is typically faster — prescriptions can be issued within days if you meet eligibility criteria.
What BMI do I need to be eligible for Mounjaro?
Generally, you need a BMI of 30 or above, or 27–29.9 if you have weight-related health conditions like diabetes, high blood pressure, or sleep apnoea. For South Asian, Chinese, Black African, or Black Caribbean adults, lower thresholds may apply. A prescriber will assess your individual case.
Can I switch from Wegovy to Mounjaro?
Yes, you can switch between GLP-1 medications with prescriber guidance, though there's no official conversion chart. Mounjaro works as a dual GIP and GLP-1 receptor agonist (different mechanism from semaglutide in Wegovy), so any switch should be managed by your healthcare provider.
Is Mounjaro the same as Ozempic?
No. Mounjaro contains tirzepatide and is licensed for weight management. Ozempic contains semaglutide and is licensed for type 2 diabetes — using it for weight loss is off-label. For weight management, the correct semaglutide product is Wegovy, which is a separate brand licensed specifically for weight loss in the UK.
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.