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
How To Buy Mounjaro Online in the UK
Mounjaro (tirzepatide) is available to buy online in the UK through private prescription pathways, following a clinical assessment with a UK-licensed prescriber. If you're wondering how to access this GLP-1 receptor agonist injection, you have two main routes: NHS specialist services or private online consultation. This guide explains both options, what to expect, eligibility requirements, and realistic costs so you can make an informed decision about whether Mounjaro is right for you.
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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 Online Access & Cost for Mounjaro in the UK
Private prescription Mounjaro is available through GPhC-registered online pharmacies without requiring NHS referral. To buy Mounjaro online, you complete an online consultation with a UK-licensed prescriber who will assess your health, BMI, medical history, and weight-related conditions. If clinically appropriate, they issue a prescription that's then dispensed by a regulated pharmacy.
Cost for private Mounjaro: Prices typically range from £120 to £320 per month depending on your dose, with most users starting at lower doses and titrating upwards over weeks. A standard maintenance dose (10–15 mg) usually costs £200–£280 monthly. Some providers offer package discounts for multiple months' supply. Remember that private costs are not covered by the NHS, so the full amount is your responsibility. Check whether your chosen provider offers flexible payment plans or subscription discounts. Our free GLP-1 weight loss calculator can help you explore potential outcomes at different doses.
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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: Which Route Is Right for You?
The NHS route involves referral from your GP to a tier 3 specialist weight management service. If approved, you pay nothing for Mounjaro itself, but waiting lists are significant in many regions—sometimes 12+ months. The private route is faster (consultation to prescription within days) but costs £120–£320 monthly. Eligibility for both routes requires a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes, hypertension, or sleep apnoea. Mounjaro vs Wegovy costs are similar privately (both £120–£320), though exact pricing varies by provider and dose. Use our free BMI calculator above to check your current BMI and explore whether you may be eligible for either route.
- 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 happens during an online Mounjaro consultation?
You complete a detailed health questionnaire covering your weight, height, BMI, medical history, medications, and any weight-related health conditions. A UK-licensed prescriber reviews your information and may request additional details (blood pressure, blood glucose history). If approved, they issue a prescription valid at regulated pharmacies. The entire process typically takes 24–48 hours.
Can I get Mounjaro on the NHS in the UK?
Yes, but access is limited. NICE has approved tirzepatide for NHS use within specialist tier 3 weight management services. You need GP referral and must meet eligibility criteria (BMI 30+, or 27–29.9 with comorbidities). NHS availability varies by region and waiting lists are often very long. Private access is faster and does not require NHS referral.
How much does a Mounjaro KwikPen cost privately?
Each KwikPen costs approximately £120–£320 depending on dose. A starting 2.5 mg pen is typically cheaper than a 15 mg maintenance pen. A standard 4-week supply (one KwikPen) at a mid-range dose costs around £200–£250. Some online providers offer monthly subscription discounts or bulk purchase savings.
What if I don't meet Mounjaro eligibility criteria?
If your BMI is below 27 or you have no weight-related health conditions, most prescribers will not issue a prescription—both NHS and private. You can explore other weight management approaches: structured diet programmes, physical activity, or speaking to your GP about tier 2 services. Check your BMI using our free BMI calculator to understand your current category.
Is Mounjaro more expensive than Wegovy online?
Pricing is similar—both typically range from £120–£320 monthly depending on dose. Costs vary between providers, so it's worth comparing. Mounjaro and Wegovy have comparable efficacy in clinical trials, though individual results vary. Your prescriber can advise which may be more suitable based on your health profile.
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.