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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Compare Mounjaro And Wegovy: UK Cost & Access
Both Mounjaro (tirzepatide) and Wegovy (semaglutide) are prescription-only weight management injections available in the UK, but they differ significantly in cost, access routes, and how you can obtain them. This guide compares both medications across NHS and private options, helping you understand eligibility, pricing, and the practical steps to access either treatment. Whether you're considering NHS specialist services or private online prescribing, we've covered everything you need to know about getting started with these GLP-1 and dual GIP/GLP-1 weight loss injections in the UK.
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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.
UK Cost & Access: Mounjaro Vs Wegovy Pricing
Private prescription costs are the most transparent access route for both medications. Mounjaro typically costs between £150–£250 per month depending on your dose, with the mounjaro kwikpen containing four weekly injections. Wegovy costs roughly £130–£200 per month at maximum dose (2.4 mg). Prices vary between different GPhC-registered online prescribing services and depend on dose level — lower starting doses cost less.
NHS access is significantly different: both medications are available through NICE-approved pathways but only via specialist tier 3 weight management services, not standard GP prescriptions. NICE has approved tirzepatide (Mounjaro) and semaglutide (Wegovy) for NHS use in adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions. However, NHS availability varies dramatically by region and waiting lists can extend many months in some areas. Your GP can refer you to your local specialist service, but access depends entirely on local commissioning decisions.
Private prescribing requires an online clinical assessment with a UK-licensed prescriber — typically costing £20–£50 — after which a prescription is issued to a GPhC-registered pharmacy. This route is faster but not available on the NHS without specialist referral. Use our free GLP-1 weight loss calculator to understand potential outcomes before committing to either option.
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: Which Route Is Right For You?
NHS route: Free on prescription once approved by your specialist service, but requires GP referral to tier 3 weight management services and can involve lengthy waits. NICE guidelines support NHS prescribing for eligible patients, but regional variation means some areas have better access than others. Mounjaro nhs nice approval and Wegovy nhs pathways both exist, but funding and availability differ.
Private route: Faster access (typically 1–2 weeks from consultation to first dose), no waiting lists, but you pay the full cost. An online consultation assesses your mounjaro uk prescription eligibility or Wegovy suitability based on your BMI, health history, and medications. You'll need a UK address and be over 18. The prescriber will check for contraindications, interactions with other medications, and confirm you're not pregnant or breastfeeding before issuing your prescription. Expect the process to take 7–10 days from initial consultation to receiving your first injection.
Both routes require clinical assessment — neither medication is available over-the-counter. Check your eligibility using our free BMI calculator to understand whether you meet the threshold for either treatment option.
- 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's the main cost difference between Mounjaro and Wegovy?
Mounjaro typically costs slightly more (£150–£250/month) than Wegovy (£130–£200/month) on private prescription, though both depend on dose level. At maximum therapeutic doses, prices are comparable. NHS access is free for both once approved, but waiting times and regional availability vary significantly across the UK.
Can I get Mounjaro or Wegovy on the NHS without private cost?
Yes, both are NICE-approved for NHS specialist weight management services, but you must be referred by your GP to tier 3 services in your area. Access depends on local commissioning and availability — some regions have shorter waits than others. Private prescription is faster but costs £130–£250/month depending on medication and dose titration progress.
How long does the private online consultation process take?
From initial consultation to receiving your first dose typically takes 7–10 days. You'll have an online assessment with a UK-licensed prescriber (£20–£50 fee), who reviews your health, BMI, medications, and eligibility. If approved, your prescription goes to a GPhC-registered pharmacy and is shipped to your home address.
What do I need for a private online prescription assessment?
You'll need to be over 18, have a UK address, and provide details of your height, weight (you can use our weight converter to switch between units), medical history, current medications, and any allergies. The prescriber will check you're not pregnant, don't have a personal or family history of thyroid cancer, and assess for any drug interactions before issuing your mounjaro uk prescription or Wegovy prescription.
Is private prescription cost covered by any UK health insurance?
Some private health insurance policies cover weight management medications, but this varies significantly by provider and policy level. Check your insurance documents or contact your provider directly. Most private prescribing costs are paid out-of-pocket. NHS access is free but requires meeting local eligibility criteria and specialist referral from your GP.
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.