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 approved and available on the NHS for weight management in adults. However, access is not through standard GP prescription — it's available through specialist tier 3 and tier 4 weight management services in NHS hospitals and clinics. NICE approved tirzepatide in 2024 for NHS use alongside lifestyle changes. Availability varies significantly by region, and waiting lists can be lengthy in many areas. Your GP can refer you to your local specialist weight management service if you meet the eligibility criteria.
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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 Mounjaro Eligibility And Access Criteria
To access Mounjaro (tirzepatide) through the NHS, you must meet specific eligibility criteria and be referred to a specialist weight management service. You may be eligible if you have a BMI of 30 or above, or 27–29.9 with at least one weight-related health condition such as type 2 diabetes, prediabetes, high blood pressure, abnormal blood fats, or obstructive sleep apnoea.
For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, lower BMI thresholds apply — eligibility may start at BMI 27.5 or above due to increased health risks at lower weights.
The NHS pathway works as follows:
- Step 1: Discuss weight management with your GP
- Step 2: Your GP refers you to your local tier 3 specialist weight management service
- Step 3: Specialist team assesses you and may prescribe Mounjaro if appropriate
- Step 4: You receive regular monitoring and support throughout treatment
Access is free once prescribed, but availability and waiting times vary dramatically across NHS regions — some services have waiting lists exceeding 12 months.
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 Access To Mounjaro In The UK
If you don't want to wait for NHS specialist services or prefer faster access, Mounjaro is also available privately through GPhC-registered online pharmacies following an online clinical assessment with a UK-licensed prescriber. Private access typically takes days to weeks rather than months, though costs vary (usually £150–£350 per month depending on dose).
Both pathways require a clinical assessment — you cannot obtain Mounjaro without a prescription from a licensed prescriber. Our GLP-1 weight loss calculator can help you estimate potential outcomes at different tirzepatide doses. Whichever route you choose, Mounjaro is most effective when combined with dietary changes, increased physical activity, and behavioural support — use our free progress tracker to monitor your weight loss journey.
- 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.
How long are NHS waiting lists for Mounjaro?
Waiting times vary significantly by NHS region. Some areas have waiting lists of 6–12 months or longer, whilst others are shorter. Contact your GP to find out current waiting times in your area, or call your local NHS weight management service directly for more recent timelines.
Can my GP prescribe Mounjaro directly, or must I go through a specialist?
Your GP cannot prescribe Mounjaro directly for weight management on the NHS. It must be prescribed through a specialist tier 3 or tier 4 weight management service. Your GP can refer you to this service, but the specialist team will conduct the assessment and prescribe if appropriate.
What's the difference between NHS and private Mounjaro access in the UK?
NHS access is free but requires specialist referral and can involve long waiting lists. Private access is faster (days to weeks) but you pay directly (typically £150–£350/month). Both require a prescription from a licensed prescriber and clinical assessment to confirm suitability.
Do I need to meet any other requirements besides BMI to get Mounjaro on the NHS?
Beyond BMI, your specialist assessment will consider your overall health, any weight-related conditions, previous weight loss attempts, and readiness to make lifestyle changes alongside medication. You'll also need to commit to regular clinic appointments and monitoring.
Is Mounjaro the same as the tirzepatide available privately, or is NHS Mounjaro different?
The medication is identical — Mounjaro is the brand name for tirzepatide regardless of whether it's prescribed via NHS or privately. The same KwikPen doses (2.5mg–15mg) and side effects apply. Only the access pathway and cost differ.
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.