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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Mounjaro Click Chart UK — Understanding Your Dose Schedule
A Mounjaro click chart shows the dose progression schedule for tirzepatide injections in the UK. If you're considering or already using Mounjaro, understanding the click chart helps you know what dose you're on and when it might be adjusted. Mounjaro is a prescription-only, once-weekly injection available in the UK for adults with obesity or overweight with weight-related health conditions. This guide explains the UK dosing schedule, how the KwikPen works, and what to expect during your treatment journey.
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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.
Mounjaro Dosing Schedule — From Start to Maximum Dose
The Mounjaro KwikPen uses a "click" system to deliver precise doses. Each click represents a specific dose, and the pen is pre-loaded with four weekly doses. In the UK, the standard Mounjaro dose progression is:
- Weeks 1–4: 2.5 mg once weekly (starting dose)
- Weeks 5–8: 5 mg once weekly (first escalation)
- Weeks 9–12: 7.5 mg once weekly (if needed)
- Weeks 13–16: 10 mg once weekly (if appropriate)
- Weeks 17–20: 12.5 mg once weekly (if appropriate)
- Week 21+: 15 mg once weekly (maximum dose)
Your prescriber must assess you after at least 4 weeks on each dose before increasing. This gradual titration helps your body adjust and reduces side effects. The KwikPen clicks once per dose delivery, making it straightforward to track which week you're on.
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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.
How the Mounjaro KwikPen Click System Works
Each Mounjaro KwikPen contains four pre-filled doses — one for each week of the month. The pen has a simple mechanical click mechanism: you dial your dose, press the injection button, and feel a click as the needle deploys. The click confirms the dose is being delivered. After each injection, store your pen at room temperature (below 30°C) until your next weekly injection. Once you've used all four doses from one pen, you'll receive a new pen for the following month. Your prescriber or pharmacy will provide detailed guidance on using your specific pen, and instructional videos are often available from the manufacturer.
- 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 there a printable Mounjaro click chart PDF for UK use?
Mounjaro click charts are typically provided by your prescriber or pharmacy rather than as standalone PDFs. However, you can request a printed dose schedule from your GP or the pharmacy supplying your medication. The standard UK progression shown above (2.5mg to 15mg over weeks) is your reference guide. Your prescriber will tell you which dose you're on and when to expect increases.
What does each click on the Mounjaro KwikPen represent?
Each click represents the full weekly dose — there's one click per injection. The KwikPen is pre-set to your prescribed dose by your pharmacy before it reaches you. You simply dial to the prescribed dose number (shown on the pen) and inject once per week. The mechanism automatically delivers the correct amount; you don't need to count multiple clicks per dose.
How do I know if my Mounjaro dose needs to increase?
Your prescriber will assess you after at least 4 weeks on each dose. They'll review your weight loss progress, how well you're tolerating the current dose, and any side effects you're experiencing. If you're tolerating the dose well and your prescriber believes a higher dose would be beneficial, they'll prescribe the next dose level. Never increase your dose without prescriber guidance.
Can I skip a Mounjaro dose if I miss my injection day?
If you miss your injection, take it within 4 days of the missed date and continue your normal schedule. If more than 4 days have passed, skip that dose and take your next dose on your normal scheduled day. Never take a double dose. If you're unsure, contact your prescriber or pharmacy for guidance.
Is Mounjaro available on the NHS in the UK?
NICE has approved tirzepatide (Mounjaro) for use within NHS specialist weight management services. However, NHS access is limited and varies significantly by region. You'll typically need a referral to a tier 3 weight management service from your GP. Private access is available through UK-licensed online prescribers following a clinical assessment.
Ready to take control of your weight loss journey?
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