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 Are the Cheapest Prices for Mounjaro in the UK?
Mounjaro costs vary significantly depending on whether you access it through the NHS or a private prescription route. On the NHS, Mounjaro is provided free at point of use through specialist tier 3 weight management services, though availability and waiting times differ across regions. Through private prescribing, costs typically range from £129 to £320 per month depending on your dose and the provider. Understanding both routes and what affects pricing can help you find the most affordable option for your situation.
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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.
NHS Access to Mounjaro — Free but with Waiting Times
On the NHS, Mounjaro (tirzepatide) is free when prescribed through specialist tier 3 weight management services. However, NHS access requires a referral from your GP and assessment by a specialist multidisciplinary team, and waiting lists vary significantly across regions — some areas have waits of several months or longer.
NICE guidance and MHRA approval: Mounjaro is approved for use within NHS weight management services under NICE guidelines for adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions. It is subject to additional MHRA monitoring (Black Triangle ▼ status).
Dose titration and treatment length: The NHS route involves dose escalation over several weeks (from 2.5 mg to a maximum of 15 mg once weekly). Treatment duration and continuation depend on specialist assessment and local formulary decisions — there is no fixed treatment length.
- Free medication at point of use
- Requires GP referral and specialist assessment
- Regional availability varies significantly
- Waiting lists can be several months in many areas
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.
Private Mounjaro Pricing — Faster Access at a Cost
Private prescriptions for Mounjaro are available through UK-licensed online prescribers and GPhC-registered pharmacies without NHS referral. Costs range from approximately £129–£320 per month depending on your starting dose and dose escalation.
Private pricing typically reflects dose strength: lower doses (2.5 mg, 5 mg) cost less than maintenance doses (10–15 mg). Some private providers offer subscription models or discounts for longer treatment periods. You'll need to complete an online clinical assessment — a UK-licensed prescriber will review your health and decide if Mounjaro is appropriate for you. Private access means faster treatment initiation but requires out-of-pocket payment unless you have private health insurance.
- No NHS waiting list — treatment can start within days
- Pricing varies by dose and provider
- Requires online clinical assessment
- Ongoing cost — not free like NHS
- 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 free?
Yes, Mounjaro is free on the NHS when prescribed through specialist tier 3 weight management services. However, you need a GP referral, specialist assessment, and must meet NICE eligibility criteria (BMI ≥30, or 27–29.9 with weight-related health conditions). NHS waiting lists vary by region.
What is the average cost of Mounjaro through private prescribing in the UK?
Private Mounjaro typically costs £129–£320 per month depending on dose. Starting doses (2.5–5 mg) are generally cheaper than maintenance doses (10–15 mg). Prices vary between providers, and some offer package discounts for longer-term treatment.
How long does it take to get Mounjaro on the NHS versus privately?
NHS access requires a GP referral and specialist assessment, which can take several months depending on your region's waiting list. Private access is faster — typically within days of completing an online clinical assessment with a UK-licensed prescriber.
What is tirzepatide, and how does it differ from other weight loss injections like Wegovy?
Tirzepatide is the active ingredient in Mounjaro. It's a dual GIP and GLP-1 receptor agonist — unlike Wegovy (semaglutide), which activates only the GLP-1 pathway. This dual mechanism may support greater appetite regulation, though individual results vary.
What should I do if I want to explore Mounjaro options?
Start by speaking to your GP about referral to tier 3 specialist services if you're interested in the NHS route. Alternatively, explore private prescribing through a UK-licensed online prescriber. Use our free GLP-1 weight loss calculator to understand projected outcomes, and our BMI calculator to check your eligibility status before seeking assessment.
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.