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
Can Doctors Prescribe Mounjaro in the UK?
Yes, doctors and GPs in the UK can prescribe Mounjaro (tirzepatide) for weight management, but access depends on which route you choose. The NHS prescribes Mounjaro through specialist tier 3 weight management services, whilst private GPs can issue prescriptions following an online clinical assessment. Understanding both routes, eligibility criteria, and what tirzepatide costs will help you decide which option suits your circumstances best.
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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 Prescription Cost & Access in the UK
Private prescription costs for Mounjaro in the UK typically range from £129 to £320 per month, depending on your starting dose and the provider. The cost reflects your weight management KwikPen, which contains four weekly injections. Prices are generally higher for maintenance doses (10–15 mg) than starter doses (2.5–5 mg). To access Mounjaro privately, you complete an online consultation with a UK-licensed prescriber, answer health questions, and receive a prescription if clinically appropriate. This prescription is then dispensed by a GPhC-registered pharmacy. The entire process typically takes 24–48 hours from consultation to delivery. Use our free GLP-1 weight loss calculator to estimate potential results at different doses, which may help you discuss expectations with your prescriber.
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: Routes to Mounjaro Prescription
NHS route: Your GP refers you to a specialist tier 3 or tier 4 weight management service. Assessment, prescription, and monitoring happen through the NHS — but waiting lists can be lengthy (months to years in many regions) and availability varies significantly by integrated care board (ICB). You will not pay directly for the medication on the NHS.
Private route: You access Mounjaro without NHS referral via private online consultation. It is faster (days rather than months) but you pay the full cost. Both routes require a UK-licensed prescriber to assess your eligibility based on BMI and health conditions. Calculate your personal BMI using our free BMI calculator to understand where you sit relative to the 30 kg/m² threshold for weight management eligibility.
- 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.
Will my GP prescribe Mounjaro on the NHS?
Your GP may refer you to specialist weight management services where Mounjaro can be prescribed on the NHS. However, you must meet eligibility criteria (BMI 30+ or 27+ with weight-related conditions) and availability depends on your local integrated care board. Waiting lists are often long. Ask your GP about NHS referral options first.
How much does Mounjaro cost privately in the UK?
Private Mounjaro prescriptions cost approximately £129–£320 per month depending on your dose, starting from 2.5 mg. The cost covers your KwikPen (four weekly injections). Maintenance doses (10–15 mg) are typically more expensive than starter doses. Prices vary slightly between providers, so compare options.
Can I get Mounjaro without seeing my GP?
Yes, you can access Mounjaro privately through an online clinical assessment with a UK-licensed prescriber, bypassing your GP. However, your prescriber will still assess your eligibility, health history, and suitability. This is not the same as obtaining medication without clinical oversight.
What is the difference between NHS and private Mounjaro?
The medication is identical; the difference is access speed and cost. NHS is free but has long waiting lists and regional variation in availability. Private is faster (days) and requires payment but does not depend on NHS referral criteria or waiting lists. Both routes involve a clinical assessment.
Is tirzepatide cheaper than Mounjaro?
Tirzepatide and Mounjaro are the same medication — Mounjaro is the brand name. Cost is determined by your prescription provider and dose, not the name. Prices are broadly similar across private providers in the UK, though worth comparing. NHS provision is free.
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.