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
Is Mounjaro Available On The NHS?
Yes, Mounjaro (tirzepatide) is available on the NHS in the UK, but access is limited and varies significantly by region. NICE approved tirzepatide for weight management in specialist NHS services, and it's prescribed through tier 3 weight management services rather than standard GP surgeries. Eligibility depends on your BMI, weight-related health conditions, and your local integrated care board (ICB) capacity. Waiting times for NHS access can be lengthy in many areas, and not all regions have equal availability. Understanding the NHS route, MHRA status, and how it compares to private access can help you decide the best option for your situation.
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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 Eligibility And Access Criteria For Mounjaro
NICE approved tirzepatide (Mounjaro) in April 2024 for use within NHS specialist weight management services. However, availability is not uniform across the UK — your local ICB determines whether Mounjaro is funded and accessible in your area.
- BMI of 30 kg/m² or above with at least one weight-related comorbidity (type 2 diabetes, prediabetes, hypertension, dyslipidaemia, cardiovascular disease, or obstructive sleep apnoea)
- BMI of 35 kg/m² or above without comorbidities
- For South Asian, Chinese, Black African, or Black Caribbean adults: lower thresholds apply (BMI 27.5+ may qualify)
- Must be referred to a tier 3 specialist multidisciplinary weight management service by your GP
- Clinical assessment by the specialist team is required before prescription
Unlike private prescribing, NHS access requires a formal referral and assessment through your local weight management service. Waiting lists vary — some areas have waits of several months to over a year. Mounjaro's KwikPen device is supplied through NHS pharmacies once prescribed, and there are no out-of-pocket costs for eligible patients.
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 Versus Private Access For Mounjaro In The UK
NHS route: Free at point of use, but requires GP referral, tier 3 specialist assessment, and potentially significant waiting times. Not available in all regions. Prescribing decisions follow NICE guidance and local ICB protocols. Once prescribed, ongoing monitoring through the NHS service is included.
Private route: Faster access (typically within days), no waiting list, available without NHS referral, but costs £129–£320+ per month depending on dose. Requires an online clinical assessment with a UK-licensed prescriber and dispensing through a GPhC-registered pharmacy. Use our free GLP-1 weight loss calculator to estimate your potential dose and costs. Both routes require tirzepatide dose titration over several weeks, starting at 2.5 mg and escalating gradually to the effective maintenance dose.
Your GP can discuss which route is most suitable for you. If NHS waiting times are lengthy in your area, private prescribing may be a faster alternative — though cost is a consideration. Some people also use the NHS pathway as a backup while pursuing private access. Whichever route you choose, Mounjaro is taken as a once-weekly injection using the KwikPen device. Track your weight loss progress using our free progress tracker, and use our BMI calculator to monitor your BMI throughout treatment, particularly if you're also making dietary and lifestyle changes.
- 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 if I have a BMI of 28?
Not typically. NICE criteria generally require a BMI of 30 or above, or 27.5+ if you're from a South Asian, Chinese, Black African, or Black Caribbean background with documented health risks. However, thresholds vary by ICB. Discuss with your GP about referral to tier 3 services — they can assess your individual circumstances and comorbidities.
How long does it take to get Mounjaro through the NHS?
Waiting times vary significantly by region. Some specialist weight management services have waits of 3–6 months, while others may be 12+ months. Factors include local demand, ICB funding, and service capacity. Private access is faster — typically available within days or weeks through online prescribing.
What's the difference between NICE approval and MHRA approval for Mounjaro?
MHRA (Medicines and Healthcare products Regulatory Agency) approved Mounjaro as safe and effective for weight management. NICE (National Institute for Health and Care Excellence) evaluated whether it represents good value for the NHS and approved its use in specialist services. MHRA approval is required for any use; NICE approval determines NHS access.
Will my GP prescribe Mounjaro directly, or do I need a specialist?
Mounjaro is prescribed through tier 3 specialist multidisciplinary weight management services, not standard GP surgeries. Your GP can refer you to your local service, but the specialist team conducts the assessment and manages ongoing prescribing and monitoring. This ensures appropriate patient selection and safety monitoring.
Can I switch between NHS and private Mounjaro prescriptions?
Technically yes, but it's not ideal. Each route involves separate prescriptions and monitoring arrangements. If you start privately and later access NHS prescribing, there would be gaps in continuity. It's best to choose one route and stick with it, or discuss transition options with both providers if circumstances change significantly.
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.