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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How Do I Get Mounjaro On The NHS?
Getting Mounjaro on the NHS in the UK is possible but involves a specific pathway through specialist weight management services. Unlike some medications available directly from your GP, Mounjaro (tirzepatide) is accessed through NHS tier 3 and tier 4 specialist services following NICE guidance. This guide explains NHS eligibility, how to get a referral, and realistic timelines. You can use our free BMI calculator above to check where you currently stand on the NHS eligibility threshold, and our GLP-1 weight loss calculator to explore potential outcomes.
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 Mounjaro Eligibility And The Specialist Services Route
To access Mounjaro through the NHS, you must be referred to a specialist tier 3 weight management service by your GP. NICE has approved tirzepatide (Mounjaro) for use within these services, meaning it is available on the NHS, but not through standard GP prescriptions.
- BMI 30 or above: You qualify for referral to tier 3 services
- BMI 27–29.9 with a weight-related health condition: Type 2 diabetes, high blood pressure, abnormal cholesterol, sleep apnoea, or cardiovascular disease
- South Asian, Chinese, Black African, or Black Caribbean heritage: Lower thresholds may apply — BMI 27.5 or above
Once referred, you'll be assessed by a multidisciplinary team (doctors, dietitians, psychologists) who will determine if Mounjaro KwikPen is appropriate for you. They will also prescribe the correct dose titration schedule and provide ongoing support with lifestyle changes. Individual results vary — clinical trials showed average weight loss of 15–21% body weight, but your outcome depends on your starting weight, adherence, and personal factors.
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 Availability And Realistic Timelines
NHS tier 3 weight management services vary significantly by region. Some areas have established services with reasonable waiting times; others have multi-month or multi-year waiting lists due to demand and limited funding. Contact your local Integrated Care Board (ICB) to check whether tier 3 services are available in your area and current waiting times.
Your GP can refer you if you meet eligibility criteria. Bring evidence of previous weight loss attempts, current health conditions, and medications to your appointment. If NHS timelines are very long or services aren't available locally, some people choose the private route — where Mounjaro is available through GPhC-registered online prescribers following a clinical assessment, with costs typically £180–£300 per month depending on dose.
- 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.
Does the NHS prescribe Mounjaro directly through my GP?
No. Mounjaro is prescribed through specialist tier 3 weight management services, not standard GP prescriptions. Your GP can refer you if you meet eligibility criteria, but the assessment and ongoing prescribing happens through the specialist service. This is standard NHS practice for weight loss medications.
What BMI do I need to qualify for NHS Mounjaro?
You need a BMI of 30 or above, or BMI 27–29.9 if you have a weight-related health condition (diabetes, high blood pressure, high cholesterol, sleep apnoea, or cardiovascular disease). For South Asian, Chinese, Black African, or Black Caribbean adults, the threshold is BMI 27.5 or above. Use our BMI calculator above to check your current status.
How long does it take to get Mounjaro through the NHS?
Waiting times vary by region. Some tier 3 services have waits of several months; others have longer delays. Contact your local Integrated Care Board to check availability and timelines in your area. Private alternatives are faster (typically 1–2 weeks from consultation to first delivery) but involve out-of-pocket costs.
What happens after referral to tier 3 services?
You'll be assessed by a multidisciplinary team (doctors, dietitians, psychologists). They will review your health, previous weight loss attempts, and medications. If approved, you'll start Mounjaro at 2.5 mg with a dose titration plan, plus support for diet and physical activity. You'll have regular follow-up appointments to monitor progress and manage any side effects.
Is Mounjaro covered by the NHS or do I pay?
Mounjaro is available on the NHS through tier 3 services — you do not pay directly for the medication if prescribed through this route. However, NHS availability is limited by regional resources and waiting lists. The private route is available but requires payment; costs typically range from £180–£300 per month depending on your dose.
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.