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 and What It Costs
If you're considering Mounjaro (tirzepatide) for weight management in the UK, understanding your access options and costs is essential. You can obtain this prescription-only medicine through either the NHS or private prescription routes, each with different timelines, eligibility requirements, and costs. This guide explains both pathways, helping you make an informed decision about which option suits your circumstances. Use our free BMI calculator above to check your eligibility, and our GLP-1 weight loss calculator to see projected results at different doses.
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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 Prescription Costs and Access in the UK
Private prescription costs for Mounjaro vary depending on the dose you're prescribed and the provider. Starting doses (2.5 mg) typically cost around £129–£180 per month, while maintenance doses (10–15 mg) range from £180–£320 per month. Each KwikPen contains 4 weekly doses, so costs cover a full month of treatment. You access private Mounjaro through an online consultation with a UK-licensed prescriber. The process involves completing a health questionnaire, a brief video or telephone consultation, and if approved, a prescription is issued to a GPhC-registered pharmacy. This route does not require a GP referral or NHS specialist appointment, making it faster than the NHS pathway. Results from clinical trials show that tirzepatide helps participants lose an average of 15–21% body weight when combined with dietary changes and increased physical activity, though individual results vary significantly.
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 Route vs Private Access — What's Best for You?
NHS access to Mounjaro is available through specialist tier 3 weight management services, but availability and waiting times vary dramatically across the UK. You'll need a GP referral to specialist services, and some regions may have waiting lists of several months to over a year. Once referred, a multidisciplinary team assesses your eligibility based on BMI, health conditions, and lifestyle factors. If approved, the NHS provides the medication free at point of use. The private route is faster (typically within 1–2 weeks) but involves upfront costs. Consider NHS access if you have significant comorbidities, prefer specialist oversight, or cannot afford private costs. Choose private if you want faster access, live in an area with limited NHS services, or prefer the convenience of online consultation. Your GP can advise on NHS availability in your area.
- 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 private prescription in the UK?
Private Mounjaro costs range from approximately £129–£180 per month for starting doses (2.5 mg) to £180–£320 for maintenance doses (10–15 mg). Each KwikPen contains 4 weekly doses, covering one month. Costs vary by provider and dose strength. Some services may offer bundle discounts for multiple months upfront.
Do I need a GP referral to get Mounjaro privately?
No. Private Mounjaro requires only an online consultation with a UK-licensed prescriber—no GP referral is needed. You complete a health questionnaire, have a brief video or telephone consultation, and if approved, your prescription is issued to a GPhC-registered pharmacy. This bypasses the NHS specialist referral pathway.
How long does it take to get Mounjaro on the NHS?
NHS timelines vary significantly by region. You'll need a GP referral to specialist weight management services, which can involve waiting lists of several months to over a year in many areas. Once referred and assessed, approval and prescription typically follow within weeks. Check NHS England's weight management services page for your local availability.
Is Mounjaro the same as Wegovy—how do they compare?
No. Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist, whilst Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials show Mounjaro achieved average weight loss of 15–21% body weight, compared to approximately 15% for Wegovy. Both require prescription and clinical assessment. Your prescriber will advise which suits you based on individual health factors.
What happens during an online consultation for private Mounjaro?
You'll complete a detailed health questionnaire covering medical history, current medications, and weight loss goals. A UK-licensed prescriber reviews this and conducts a brief video or telephone consultation to confirm suitability. If approved, your prescription is sent to a GPhC-registered pharmacy, and medication is delivered to your address. The entire process typically takes 1–2 weeks.
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.