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
What Does Mounjaro Cost for Weight Loss in the UK?
Mounjaro (tirzepatide) is a prescription-only weekly weight loss injection available in the UK through both NHS specialist services and private prescribing. Costs vary significantly depending on whether you access it through the NHS or privately. If you're eligible, your GP can refer you to a specialist weight management service, though waiting times can be considerable in many regions. Alternatively, private online consultations offer faster access. Understanding both routes and their costs helps you make an informed decision about whether this medication is right for you.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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 costs for Mounjaro typically range from £130 to £320 per month, depending on your dose and the provider. The lowest dose (2.5 mg) costs less than higher doses, since you pay per injection and titrate upwards over several weeks. A standard KwikPen contains four weekly doses.
Most private providers quote per dose rather than per month. At the starting dose of 2.5 mg, you might pay around £30–50 per injection. Maintenance doses (10–15 mg) typically cost £80–150 per injection. These are approximate figures — prices vary between GPhC-registered online pharmacies and private weight management clinics.
- Starting dose (2.5 mg): approximately £30–50 per week
- Escalation doses (5–10 mg): approximately £50–100 per week
- Maximum dose (15 mg): approximately £100–150 per week
You will also need to factor in the cost of the initial online consultation (typically £30–80) and follow-up consultations or monitoring (£20–50 per visit) if required by your provider. Unlike some medications, Mounjaro is not available on NHS prescription through standard GP prescribing — access is restricted to specialist weight management services.
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 Access vs Private Access to Mounjaro
NHS access to Mounjaro is free at point of use but involves a different pathway. NICE has approved tirzepatide for use within NHS specialist tier 3 and tier 4 weight management services. However, you cannot simply ask your GP for a Mounjaro prescription — you must be referred to a specialist service, which typically serves adults with a BMI of 35 or above, or 30+ with weight-related health conditions like type 2 diabetes or hypertension.
The challenge with NHS access is availability and waiting times. Many integrated care boards (ICBs) have long waiting lists — sometimes months to over a year — and some regions have limited or no specialist services. Private access offers faster outcomes. Following an online consultation with a UK-licensed prescriber, you can receive a prescription within days if clinically appropriate, then collect from a GPhC-registered pharmacy. This route suits those who cannot access NHS services quickly or who prefer privacy and convenience.
- 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.
Is Mounjaro available on the NHS for weight loss?
Yes, NICE has approved Mounjaro for NHS specialist weight management services. However, access is limited to tier 3/4 specialist services, not standard GP prescribing. You need a referral and typically a BMI of 30+ with comorbidities (or 35+). Waiting times vary significantly by region.
How much does a Mounjaro KwikPen cost privately in the UK?
A KwikPen (four weekly doses) costs approximately £120–600 depending on the dose strength. Starting doses cost less; maximum doses (15 mg) cost more. Prices are set by individual providers and vary between GPhC-registered pharmacies.
What is included in the cost of private Mounjaro treatment?
The weekly injection cost is separate from consultation fees (£30–80 initial, £20–50 follow-up). Some providers offer bundled packages including clinical review. Check with your provider what monitoring and support are included.
Why does Mounjaro cost more at higher doses?
You pay per injection, not per month. Lower starting doses (2.5 mg) are cheaper; higher doses used during titration and maintenance cost more. This reflects the graduated dose escalation recommended during the first 20 weeks of treatment.
Can I use a prescription weight loss calculator to estimate Mounjaro costs?
Our GLP-1 weight loss calculator helps you explore different doses and timelines, which can inform cost planning. However, final costs depend on your chosen provider and may include consultation and monitoring fees beyond the injection cost alone.
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.