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
What Does Mounjaro Cost Per Month in the UK?
Mounjaro (tirzepatide) in the UK costs between £129 and £320 per month through private prescription, depending on your dose and which GPhC-registered pharmacy you use. On the NHS, it's free but access is limited to specialist weight management services and varies significantly by region. This guide explains both routes, what you'll pay, and how to access this prescription weight loss injection in the UK.
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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 for Mounjaro in the UK
Private Mounjaro costs vary by dose and provider:
- Starting doses (2.5 mg): typically £129–£180 per month
- Maintenance doses (5–10 mg): typically £180–£250 per month
- Higher doses (12.5–15 mg): typically £250–£320 per month
Each KwikPen contains four weeks of doses, making monthly costs straightforward to calculate. Prices depend on your pharmacy and whether they offer any package discounts for longer-term treatment. When getting a private prescription through an online consultation, you'll receive a quote before paying. The prescription-only status means you cannot purchase Mounjaro without a UK-licensed prescriber's assessment. Using our GLP-1 weight loss calculator, you can estimate potential weight loss at your dose to understand the value relative to cost.
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 in the UK
NHS Route: Free but limited. NICE has approved tirzepatide (Mounjaro) for NHS specialist tier 3 weight management services. However, access varies dramatically by region—some areas have long waiting lists of months or even years, and not all ICBs (Integrated Care Boards) fund it immediately. You'll need a GP referral to specialist services.
Private Route: Available now through GPhC-registered online pharmacies following a clinical assessment. Faster access, no referral needed, but you pay the full cost. Most people choose private access due to NHS waiting times. Both routes require a prescription from a UK-licensed prescriber who assesses your BMI, health conditions, and medications.
What to expect in the private prescription process: You complete an online health questionnaire, a prescriber reviews your details (usually within 24 hours), and if approved, your prescription is sent to an NHS pharmacy partner for dispensing. Your medication arrives within 2–5 working days. Costs are quoted upfront—no hidden charges. Track your progress with our free progress tracker to monitor results and discuss outcomes with your prescriber at follow-up consultations.
- 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 available on the NHS in the UK?
Yes, NICE has approved tirzepatide for NHS use, but access is through specialist tier 3 weight management services and is not universally available. Availability depends on your region and ICB. Your GP can refer you if you're eligible, but waiting times can be very long. Private prescription access is often faster.
How much does a single Mounjaro KwikPen cost?
A KwikPen contains four weekly doses. At starting doses (2.5 mg), expect £129–£180 for the pen; at maintenance doses (10 mg), expect £180–£250. At maximum doses (15 mg), expect £250–£320. Costs vary by pharmacy and any available discounts for multi-month treatment.
What affects the price of Mounjaro in the UK?
The main factors are your current dose (higher doses cost more), which pharmacy you use, whether you're buying single pens or committing to longer-term treatment, and any package or loyalty discounts. The KwikPen itself has the same list price; variation comes from how pharmacies price their service and consultations.
Can I use my private health insurance to cover Mounjaro?
Most standard private health insurance plans don't cover weight management injections unless you have a specific obesity treatment policy. Check your policy documents or contact your provider directly. Some insurers may offer partial cover if prescribed through a private consultant.
How do I get a private Mounjaro prescription in the UK?
Register with a GPhC-registered online pharmacy, complete a health questionnaire, and wait for a UK-licensed prescriber to assess you. If approved, you'll receive a prescription and cost quote. Payment is made to the pharmacy, and your medication is dispensed via an NHS partner pharmacy and delivered to your address within days.
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.