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
Can You Get Mounjaro On The NHS In The UK?
Yes, Mounjaro (tirzepatide) is available on the NHS in the UK, but access is limited and varies significantly by region. It's prescribed through specialist tier 3 or 4 weight management services, not by standard GP prescription. NICE (the National Institute for Health and Care Excellence) has approved tirzepatide for use within NHS weight management programmes for eligible adults with obesity or overweight with related health conditions. However, NHS availability is restricted, waiting lists can be very long, and not all areas offer it. Many people choose private prescription as an alternative.
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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 Access: How It Works And What You Need To Know
NHS access to Mounjaro is through specialist weight management services only. You cannot get a Mounjaro prescription from your GP directly. Instead, your GP must refer you to a tier 3 or tier 4 specialist multidisciplinary weight management service in your area. These services are commissioned by Integrated Care Boards (ICBs) across England, and availability varies widely by region.
Eligibility criteria for NHS Mounjaro:
- BMI of 30 kg/m² or above, OR
- BMI of 27–29.9 kg/m² with at least one weight-related health condition (type 2 diabetes, hypertension, dyslipidaemia, sleep apnoea, or cardiovascular disease)
- Lower thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults (BMI 27.5 or above)
- Previous attempts at weight management including lifestyle changes
The waiting list for NHS specialist services can be several months to over a year in many regions. Use our free BMI calculator above to check your eligibility first.
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 Mounjaro Prescription: Cost, Access, And The Online Route
Private Mounjaro prescriptions offer faster access than the NHS. Available through GPhC-registered online pharmacy services, you can obtain a prescription without an NHS referral. The process involves an online clinical assessment with a UK-licensed prescriber, who evaluates your health, BMI, and suitability for the medication. If approved, a prescription is issued and the Mounjaro KwikPen is dispensed by post.
Private costs typically range from £129–£320+ per month depending on the dose (starting at 2.5 mg, escalating to 15 mg maximum). Each KwikPen contains four weekly injections. Compare this to the time and uncertainty of NHS waiting lists. Try our free GLP-1 weight loss calculator to estimate potential outcomes and help inform your decision between NHS and private routes.
- 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 does it take to get Mounjaro on the NHS?
Waiting times vary by region. Some areas have waiting lists of 6–12 months or longer. Tier 3 services are typically faster than tier 4 (bariatric surgery pathways). Contact your local Integrated Care Board to check current waiting times in your area. Private prescription is available within days by contrast.
What's the difference between NHS and private Mounjaro?
The medication itself is identical. The difference is access speed, cost, and oversight. NHS is free at point of use (funded by taxes) but has long waits and regional variation. Private costs £129–£320+ monthly but is available immediately after online clinical assessment. Both require a prescription from a licensed prescriber.
Will my GP refer me to a weight management service for Mounjaro?
Your GP can refer you if you meet eligibility criteria (BMI ≥30 or ≥27 with health conditions). However, GPs do not prescribe Mounjaro directly — referral to specialist tier 3/4 services is required. Some GP practices may be reluctant to refer if local waiting lists are extremely long. Ask your GP about referral eligibility and local waiting times.
Is tirzepatide (Mounjaro) the same as semaglutide (Wegovy)?
Both are weight loss injections, but they're different medications. Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist. Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials show both support weight loss, but Mounjaro appears to achieve slightly higher average weight loss in some studies. Eligibility and costs differ between the two.
Can I switch from NHS Mounjaro to private, or vice versa?
Yes, you can transition between NHS and private prescriptions. If you start on NHS and the waiting list becomes unmanageable, you can pursue private prescription. Conversely, if you access private Mounjaro and later become eligible for NHS, you can transfer to NHS care. Any switch should be discussed with your prescriber to ensure continuity of care and appropriate dose titration.
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.