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 5mg Cost in the UK?
Mounjaro 5mg is the first standard maintenance dose of tirzepatide available in the UK, but the cost varies significantly depending on whether you access it through the NHS or privately. Private Mounjaro costs typically range from £150 to £250 per KwikPen (4-week supply) depending on the provider, while NHS access is free at the point of use — though availability is limited and regional. Understanding the full cost picture, including what the dose does and your eligibility, can help you make an informed decision about whether this medication 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.
Mounjaro 5mg Private Prescription Cost in the UK
Private Mounjaro 5mg costs vary between providers but typically range from £150 to £250 per KwikPen. Each pen contains 4 doses (4 weeks' supply), so monthly costs are roughly in this bracket. Some providers may offer multi-month discounts — it's worth comparing prices across GPhC-registered online pharmacies. The 5mg dose is usually reached by week 5 of treatment, after starting at 2.5mg for 4 weeks. At this point, many patients find it to be the first maintenance dose where they begin to see meaningful effects. Private prescription costs include the prescriber's consultation fee (typically £20–£40), plus the pharmacy dispensing fee, so total first-month costs may be slightly higher. Always check whether the price quoted includes both the prescription assessment and the medication itself.
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 to Mounjaro and Cost Considerations
On the NHS, Mounjaro is free once prescribed, but access is limited to specialist tier 3 weight management services rather than standard GP prescriptions. NICE has approved tirzepatide (Mounjaro) for weight management, but NHS availability varies significantly by region and depends on your local integrated care board (ICB) funding and waiting list capacity. Many areas have waiting lists of several months to over a year. If you don't meet NHS criteria or face long waits, private prescription may be an alternative — though at a cost. Use our GLP-1 weight loss calculator to estimate potential outcomes, then discuss both NHS and private options with your GP to find the most suitable route for you.
- 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 5mg the starting dose?
No. Mounjaro starts at 2.5mg for weeks 1–4, then increases to 5mg for weeks 5–8. The 5mg dose is the first standard maintenance dose. Patients typically stay on 5mg for at least 4 weeks before escalating further, depending on their response and tolerability.
How long does one Mounjaro KwikPen last?
Each KwikPen contains 4 doses, lasting exactly 4 weeks (one injection per week). At the 5mg dose, one pen lasts 28 days. You'll need to order a new pen around day 25–26 to ensure continuity of treatment.
Does the NHS cover Mounjaro 5mg?
Yes, Mounjaro is free on the NHS if prescribed through a specialist tier 3 weight management service. However, NHS access is not available through standard GP prescription — you must be referred to and assessed by a specialist service. Availability and wait times vary dramatically by region.
Can I get Mounjaro 5mg without a prescription?
No. Mounjaro is a prescription-only medicine in the UK. You must have a clinical assessment from a UK-licensed prescriber before it can be prescribed. Private online prescribers can assess you without an NHS referral, but a valid prescription is always required.
How does the cost of Mounjaro 5mg compare to Wegovy?
Mounjaro (tirzepatide) and Wegovy (semaglutide) have similar private costs — roughly £150–£250 per month depending on dose and provider. Mounjaro's 5mg dose and Wegovy's 1–1.7mg dose are approximate maintenance equivalents, though individual costs vary. Compare providers directly for current pricing.
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.