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
Mounjaro (tirzepatide) is a prescription-only GLP-1 weight loss injection available in the UK through both NHS specialist services and private online prescribing. Access routes differ significantly — NHS availability is limited and varies by region, whilst private prescription offers faster access but at a cost. Understanding your options, eligibility, and what to expect during an online clinical assessment will help you make an informed decision about whether Mounjaro is right for your weight management journey. Our GLP-1 weight loss calculator can help you estimate potential outcomes 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 Mounjaro Costs and How to Access It
Private prescription costs in the UK typically range from £120 to £290 per month, depending on your dose and the prescribing service. Each Mounjaro KwikPen contains four weekly injections — so prices reflect a 4-week supply.
- Starting doses (2.5 mg): approximately £129–£150 per month
- Mid-range doses (5–10 mg): approximately £180–£220 per month
- Maximum dose (15 mg): approximately £250–£290 per month
Private access requires an online consultation with a UK-licensed prescriber. You'll complete a health questionnaire, discuss your weight loss goals and medical history, and the prescriber will assess whether tirzepatide is suitable for you. If approved, a prescription is issued to a GPhC-registered pharmacy, and your medication is dispatched within 1–2 working days. Unlike NHS services, private prescription doesn't require a GP referral, making it significantly faster — many people access their first dose within 5–7 days of initial consultation.
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 access to Mounjaro is available through specialist tier 3 and tier 4 weight management services, but only after referral from your GP. NICE has approved tirzepatide for NHS use, yet regional availability is extremely limited — some integrated care boards (ICBs) have lengthy waiting lists (6–12 months or longer), whilst others have no current provision. You'll need a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or cardiovascular disease.
Private access bypasses NHS waiting lists entirely. You pay upfront but receive your prescription much faster. Both routes require clinical assessment — the difference is speed, cost, and who conducts the assessment.
- 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 privately per month in the UK?
Private Mounjaro typically costs £120–£290 per month depending on dose. Starting dose (2.5 mg) is around £129–£150. Mid-range doses (5–10 mg) are £180–£220. Maximum dose (15 mg) is £250–£290. Each supply is a 4-week KwikPen with four injections.
Can I get Mounjaro on the NHS in the UK?
Yes, NICE has approved tirzepatide for NHS use through specialist weight management services. However, availability varies significantly by region. Most require GP referral to tier 3 services, and many areas have long waiting lists (6–12 months). Check with your local integrated care board for current availability.
What happens during a private Mounjaro online consultation?
You complete a health questionnaire covering weight, medical history, medications, and weight loss goals. A UK-licensed prescriber reviews your answers, may ask follow-up questions via video or phone, and assesses if Mounjaro is suitable. If approved, a prescription is issued to a GPhC pharmacy within hours. This entire process typically takes 24–48 hours.
How quickly can I start Mounjaro if I go private?
Private Mounjaro is typically much faster than NHS. After your online consultation is approved (24–48 hours), your prescription is sent to a pharmacy, and medication dispatches within 1–2 working days. Many people receive their first dose within 5–7 days of initial contact.
Do I need a GP referral to get Mounjaro privately?
No. Private online prescribing does not require GP referral. You book a consultation directly with a GPhC-registered online service, complete an assessment, and if approved, receive a prescription. You don't need to involve your GP, though you may wish to inform them if you start 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.