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
Where to Get Mounjaro in the UK
If you're looking for Mounjaro (tirzepatide) in the UK, you have two main routes: NHS specialist services or private prescription through an online clinical assessment. Access, costs, and waiting times differ significantly between the two options. This guide explains how each pathway works, what you'll need, and what to expect so you can make an informed decision about your weight management options.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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 Route — Cost and Access
The private route is the most straightforward way to access Mounjaro quickly in the UK. Private prescription costs typically range from £129 to £320 per month, depending on your dose and which provider you choose. Mounjaro comes as a pre-filled KwikPen containing four weekly injections, so monthly costs reflect this four-week supply.
- Starting dose (2.5 mg) is usually at the lower end of the cost range
- Higher doses (10 mg–15 mg) cost more per month
- You'll need an online clinical assessment with a UK-licensed prescriber
- GPhC-registered pharmacies dispense prescriptions following assessment
- Prescriber will review your BMI, health history, and contraindications
- Results from our free BMI calculator can help you prepare for your consultation
The entire process from initial consultation to receiving your first prescription typically takes 1–3 working days. No NHS referral is required — you access this privately without going through your GP.
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 — Access, Eligibility, and Waiting Times
NICE approved tirzepatide (Mounjaro) for use within NHS specialist weight management services, but NHS access is not through your GP. You'll need referral to a tier 3 or tier 4 specialist weight management service, usually by your GP based on your BMI and comorbidities. Mounjaro is free at point of use on the NHS, but waiting lists vary dramatically by region — some ICBs have waits of 6–18 months or longer.
- Your GP assesses eligibility and makes the referral
- Specialist service conducts full assessment before prescription
- Free on NHS once prescribed, but no assured timeline
- Availability depends on your local Integrated Care Board (ICB)
- Some regions have very limited access or extended waiting lists
Check what's available in your area by contacting your local weight management service directly or asking your GP.
- 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 cheaper on the NHS or private?
Mounjaro is free on the NHS once prescribed, but waiting lists can be very long (6–18 months in many areas). Private prescriptions cost £129–£320 per month but are available within days. The NHS option is cheaper financially but slower. Private is faster but has upfront costs.
Do I need a prescription to get Mounjaro?
Yes. Mounjaro is prescription-only in the UK. You cannot buy it over the counter. Private access requires an online clinical assessment with a UK-licensed prescriber who will issue a prescription if appropriate. NHS access requires a GP referral and specialist assessment.
What happens during a private online consultation for Mounjaro?
A UK-licensed prescriber reviews your medical history, current medications, weight, height, and BMI. They'll ask about any contraindications (pregnancy, allergy to tirzepatide, gallbladder issues). If clinically suitable, they issue a prescription to a GPhC-registered pharmacy. The whole consultation takes 15–30 minutes online.
Can I get Mounjaro through my GP?
Standard GP practices do not typically prescribe Mounjaro. You can ask your GP for an NHS referral to a specialist weight management service, but this goes through tier 3/4 services, not primary care. Private prescribing via online consultants is an alternative route that does not involve your GP.
How does Mounjaro compare to Wegovy for cost and access in the UK?
Both Mounjaro and Wegovy are prescription-only and available through private online consultation at similar costs (£129–£320/month depending on dose). Mounjaro is a dual GIP/GLP-1 agonist while Wegovy is GLP-1 only. Both require clinical assessment. NHS access for both is through specialist services with variable waiting times. ```
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.