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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Mounjaro Diet Injection — How to Access and Cost in the UK
Mounjaro (tirzepatide) is a prescription-only weekly weight loss injection available in the UK through both NHS specialist services and private prescription routes. The cost and access pathway vary significantly depending on whether you pursue NHS or private prescription. This guide explains how to access Mounjaro in the UK, what to expect from each route, and the typical cost context to help you understand your options. Your eligibility depends on your BMI, health conditions, and individual circumstances assessed by a licensed prescriber.
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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.
Private Mounjaro Costs and UK Availability
Private prescription costs for Mounjaro vary by dose and provider, typically ranging from £120 to £300+ per month depending on the starting dose (2.5 mg) through to the maximum maintenance dose (15 mg). A single KwikPen contains 4 weekly doses, so costs scale with your current dose level. Prices also depend on the online prescribing service used — different GPhC-registered pharmacies set their own rates, though all are UK-regulated and require a clinical assessment before dispensing. Unlike NHS provision, private prescription Mounjaro is available without waiting lists, and you can begin treatment within days of completing a consultation. Your prescriber will assess your eligibility based on your BMI, weight-related health conditions, and medical history through a secure online consultation, similar to other prescription services in the UK. Storage costs are minimal — Mounjaro must be kept refrigerated before first use and can be stored at room temperature for up to 30 days after opening.
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 Access to Mounjaro
NHS route: Mounjaro is available through NICE-approved tier 3 specialist weight management services, but access depends on regional commissioning and availability varies across ICBs. NHS referral typically requires assessment by your GP first, followed by a referral to your local specialist service — the process can take several months and waiting lists are often substantial. Once prescribed through the NHS, Mounjaro is free on prescription.
Private route: Available immediately through online consultations with UK-licensed prescribers at GPhC-registered pharmacies. No GP referral needed. You pay per dose, but treatment begins quickly. This route suits those unable to access NHS services or who prefer not to wait. Both routes require a genuine clinical assessment — no legitimate UK provider will prescribe without evaluation.
- 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 per month in the UK?
Private costs typically range from £120–£300+ monthly depending on your current dose level. A starting dose (2.5 mg) costs less than maintenance doses (10–15 mg). Prices vary between providers but all are regulated. NHS prescriptions are free once approved by a specialist service, though waiting times vary regionally and can be lengthy.
Can I get Mounjaro on the NHS in the UK?
Yes — Mounjaro is NICE-approved for NHS specialist weight management services. You'll need a GP referral to tier 3 services, clinical assessment, and approval based on your BMI and weight-related health conditions. Availability and waiting times vary significantly by region (ICB). Once approved, it's free on prescription.
How do I access Mounjaro privately in the UK?
Complete an online consultation with a UK-licensed prescriber through a GPhC-registered pharmacy. You'll answer health questions, and the prescriber assesses your eligibility. If approved, your prescription is dispensed and delivered. The process typically takes 24–48 hours from consultation to delivery.
Is Mounjaro more effective than Wegovy for weight loss?
Clinical trials show Mounjaro (dual GIP+GLP-1) produces slightly higher average weight loss (15–21% body weight) compared to Wegovy (approximately 15% body weight). However, individual results vary significantly. A prescriber can help you choose which is more suitable based on your health profile.
What happens after I start Mounjaro — do I need ongoing prescriptions?
Yes — you'll continue weekly injections and need ongoing prescriptions as long as you're taking the medication. Private users reorder through their provider. NHS patients attend specialist clinic appointments for monitoring. You can stop at any time, though weight may return if lifestyle changes aren't maintained alongside treatment.
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.