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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Mounjaro Prices Compare in the UK
Mounjaro (tirzepatide) costs vary significantly depending on whether you access it through the NHS or privately in the UK. NHS access is through specialist weight management services and is free at point of care, though availability is limited and waiting times are often lengthy. Private prescription costs typically range from £129 to £320 per month depending on your dose and provider. Understanding both routes, eligibility criteria, and what to expect during a clinical assessment can help you make an informed decision about accessing this 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.
Private Mounjaro Costs in the UK
Private prescription Mounjaro costs vary by dose and provider. The starting dose (2.5 mg) is typically the most affordable, usually between £129–£160 per month, whilst higher maintenance doses (10–15 mg) generally cost £250–£320 per month. Each KwikPen contains 4 weeks of doses, so monthly cost reflects a 4-week supply. Costs may include the prescriber consultation fee (usually £20–£50) plus the medication itself. Some private providers offer package discounts if you commit to multiple months upfront. It's important to compare pricing across multiple GPhC-registered pharmacies, as costs vary. Before starting any prescription medication, you'll need an online clinical assessment with a UK-licensed prescriber to confirm you meet eligibility criteria. Use our GLP-1 weight loss calculator to estimate potential outcomes at different doses, helping you decide if the investment aligns with your weight management goals.
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 for Mounjaro
NHS Mounjaro access is free but limited in availability. NICE (National Institute for Health and Care Excellence) has approved tirzepatide for NHS use through tier 3 specialist weight management services. However, access varies dramatically by region (Integrated Care Board), and many areas have significant waiting lists—sometimes 6–18 months. You typically need a GP referral to specialist services. Private access is faster but requires payment. Through private online prescribing with a GPhC-registered pharmacy, you can access Mounjaro within days of your clinical assessment, without NHS referral. The private route suits those who want quicker access or live in areas with limited NHS provision. Both routes require a thorough clinical assessment to confirm eligibility based on your BMI, health conditions, and medical history.
- 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.
What is the average cost of Mounjaro per month in the UK privately?
Private Mounjaro costs typically range from £129–£160 per month for starting doses (2.5–5 mg) up to £250–£320 for higher maintenance doses (10–15 mg). Costs vary by provider and may include a prescriber consultation fee. Always compare prices across GPhC-registered pharmacies, as pricing differs.
Is Mounjaro available on the NHS in the UK?
Yes, NICE has approved tirzepatide (Mounjaro) for NHS specialist weight management services. It's free at point of care, but availability is limited by region. You'll need a GP referral to tier 3 specialist services, and waiting lists can be 6–18 months depending on your area.
What's the difference between NHS and private Mounjaro access?
NHS access is free but involves waiting lists and regional variation in availability. Private access through GPhC-registered pharmacies costs £129–£320/month but is faster (days vs months). Both require clinical assessment; NHS requires GP referral; private does not.
Do I need a prescription to buy Mounjaro in the UK?
Yes, Mounjaro is prescription-only in the UK. You cannot buy it without a valid prescription from a UK-licensed prescriber. Both NHS and private routes require clinical assessment to confirm eligibility before a prescription is issued.
How does Mounjaro compare in cost to Wegovy?
Both are similar in price range. Mounjaro typically costs £129–£320/month privately depending on dose. Wegovy (semaglutide) costs similarly, around £129–£300/month for equivalent doses. Individual prescriber and pharmacy pricing varies, so comparison shopping is recommended.
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.