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 in the UK?
Yes, Mounjaro (tirzepatide) is available on the NHS in the UK for weight management, but access is limited to specialist tier 3 and tier 4 weight management services rather than standard GP prescription. NICE has approved tirzepatide for use within these specialist services. However, NHS availability varies significantly by region, and waiting lists can be lengthy in many areas. Private access through licensed UK prescribers is also available as an alternative route. Understanding your NHS options and eligibility is the first step toward exploring this prescription-only weight loss medication.
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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 Access and How Mounjaro Prescription Works in the UK
Mounjaro is not prescribed by your GP directly. Instead, access is through specialist weight management services (tier 3 or tier 4) within your local NHS Integrated Care Board (ICB). You typically need a referral from your GP to these services, though some areas now accept direct self-referral. Once referred, you'll be assessed by a multidisciplinary team including doctors, dietitians, and psychologists before a prescription is issued.
NICE approved tirzepatide (the active ingredient in Mounjaro) for NHS use in weight management following clinical evidence. However, NHS provision is not standardised across all regions — some areas have good availability, while others have very long waiting lists or limited access. The Mounjaro KwikPen is provided on prescription if approved, though this depends on your local ICB's formulary decisions. You can check your local NHS weight management service's contact details through your GP surgery or online.
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.
Who Is Eligible for NHS Mounjaro and Private Alternatives
You may be eligible for NHS Mounjaro if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions (such as type 2 diabetes, prediabetes, high blood pressure, or cardiovascular disease). Lower BMI thresholds apply if you're of South Asian, Chinese, Black African, or Black Caribbean heritage. Calculate your BMI using our free BMI calculator above to see where you fall.
If NHS waiting lists are long in your area, private access is available through UK-licensed online prescribers following a clinical assessment. This offers faster access without NHS referral, though you pay privately. Both routes require a clinical assessment to confirm suitability — tirzepatide is prescription-only and not everyone is eligible. Discuss your options with your GP, who can advise on both NHS and private pathways.
- 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 is the NHS waiting list for Mounjaro?
Waiting times vary significantly by region. Some areas have waiting lists of several months to over a year for specialist weight management services. Contact your local NHS weight management service or ask your GP for current waiting times in your area. If waiting times are very long, private access may be worth exploring.
Do I need a GP referral to access NHS Mounjaro?
Most areas require a GP referral to specialist weight management services. However, some NHS trusts now accept direct self-referral. Check with your local ICB or search "weight management services near me" on the NHS website. Your GP can tell you how referrals work in your area.
What's the difference between NHS and private Mounjaro prescriptions?
NHS prescriptions are through specialist services (tier 3/4) and are free once approved. Private prescriptions come from licensed online prescribers and require payment. Private access is typically faster but costs £150–£300+ per month depending on dose. Both require clinical assessment and are prescription-only.
Will the NHS cover Mounjaro if I'm overweight but not obese?
Yes, if your BMI is 27–29.9 and you have weight-related health conditions (like prediabetes or high blood pressure). Lower thresholds apply for South Asian, Chinese, Black African, or Black Caribbean adults. Use our GLP-1 weight loss calculator to see projected outcomes and discuss eligibility with your GP.
Is Mounjaro the same as Wegovy on the NHS?
Both are prescription-only weight loss medications licensed in the UK. Mounjaro (tirzepatide) is a dual GIP/GLP-1 agonist; Wegovy (semaglutide) is a GLP-1 agonist only. Both may be available through NHS specialist services, but which one is prescribed depends on clinical assessment and your local ICB's formulary decisions.
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.