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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How to Access Mounjaro in the UK
Mounjaro (tirzepatide) is available in the UK through both NHS specialist services and private prescribing, but access routes, costs, and waiting times differ significantly. Understanding your options helps you make an informed decision about whether this prescription weight loss injection is right for you. This guide covers NHS eligibility, private costs, and how the prescription process works 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.
Mounjaro Cost and Private Access in the UK
Private prescription costs: Mounjaro prescribed through private online consultations typically costs between £129 and £320 per month, depending on your dose. A Mounjaro KwikPen contains four weekly doses, so costs reflect the full monthly supply. Starting doses (2.5 mg) are usually cheaper than maintenance doses (10–15 mg).
- Each pen lasts 4 weeks (one injection per week)
- Costs vary between UK prescribing providers
- Private prescriptions require an online clinical assessment
- You'll need a valid UK prescription to collect from a GPhC-registered pharmacy
Private access means you can start treatment immediately without NHS waiting lists, though you pay the full cost. When comparing Mounjaro vs other weight loss options like Wegovy, remember that Mounjaro is a dual GIP/GLP-1 receptor agonist — a different mechanism from standard GLP-1 injections.
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 Route — What's the Difference?
NHS route: Mounjaro is available on the NHS through tier 3 and tier 4 specialist weight management services. You'll need a referral from your GP, but the medication is free once prescribed. However, waiting lists for NHS specialist services vary significantly by region — some areas have waits of 6–18 months or longer.
Private route: You can access Mounjaro without an NHS referral by having an online consultation with a UK-licensed prescriber. A clinical assessment takes 10–20 minutes, and if approved, your prescription is sent to a GPhC-registered pharmacy for dispensing. This typically takes 24–48 hours. The Mounjaro dose titration schedule remains the same regardless of route — you'll start at 2.5 mg and increase weekly as your body adjusts.
- 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.
How much does Mounjaro cost on the NHS?
Mounjaro is free on the NHS once prescribed through a specialist weight management service. However, you must be referred by your GP and meet eligibility criteria (BMI ≥30, or ≥27 with weight-related health conditions). Regional availability varies significantly.
Can I get Mounjaro on prescription without the NHS?
Yes. UK-licensed prescribers can issue private prescriptions following an online clinical assessment. You'll pay privately (typically £129–£320/month depending on dose) and collect from a GPhC-registered pharmacy.
How long does a private Mounjaro prescription take?
The online consultation typically takes 10–20 minutes. If approved, your prescription goes to a pharmacy within hours. Delivery usually takes 24–48 hours. This is faster than NHS routes which often have several-month waiting lists.
What's the difference between private Mounjaro and NHS Mounjaro?
The medication is identical. The difference is access speed and cost. NHS is free but may involve waiting lists; private costs £129–£320/month but offers immediate access. Clinical assessment and dose titration are the same on both routes.
How do I compare Mounjaro with other weight loss injections like Wegovy?
Use our free GLP-1 weight loss calculator to estimate potential outcomes at different doses. Mounjaro is a dual GIP/GLP-1 agonist (stronger appetite suppression), while Wegovy is GLP-1 only. Clinical trials show similar average weight loss (~15–21%), but individual results vary significantly.
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.