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 — Complete UK Dosing Guide
A Mounjaro "click chart" refers to the graduated dose progression of tirzepatide when using the KwikPen pre-filled injection device. Each click delivers a specific dose, escalating weekly over several months. Understanding your dose schedule is important for managing expectations and side effects. This guide explains how the Mounjaro dose titration works in the UK, what each dose represents, and how prescribers determine whether to increase your dose.
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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 Dose Schedule — Click-by-Click Breakdown
Mounjaro comes as a pre-filled KwikPen injection device. Each pen delivers four weekly doses — you inject once per week for four weeks, then open a new pen. The dose escalation happens gradually over approximately 20 weeks, allowing your body to adjust.
- Weeks 1–4: 2.5 mg (starting dose)
- Weeks 5–8: 5 mg (first escalation)
- Weeks 9–12: 7.5 mg (further escalation)
- Weeks 13–16: 10 mg (continued escalation)
- Weeks 17–20: 12.5 mg (pre-maximum dose)
- Week 21+: 15 mg (maximum maintenance dose)
Your prescriber may keep you at any dose if you're tolerating it well and seeing good results. You don't automatically progress to the maximum dose — titration is personalised. Clinical trials showed average weight loss of approximately 15–21% body weight across all doses, though individual results vary significantly.
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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.
Why Gradual Dose Titration Matters
Gradually increasing the dose helps your body adapt and typically reduces side effects. Nausea, diarrhoea, and stomach discomfort are common when starting any GLP-1 or GIP/GLP-1 medication, but often improve as your body adjusts. By increasing slowly every four weeks, many people find side effects manageable.
Each dose increase happens only if you've been stable on the previous dose for at least four weeks. Your prescriber will assess how you're tolerating the medication and whether weight loss is progressing before recommending an increase. Some people stay on lower doses (5–10 mg) because they achieve good results and prefer fewer side effects than they might experience at higher doses. There's no pressure to reach 15 mg — your dose should be right for you.
- 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 many clicks does each Mounjaro dose require?
Each KwikPen has a dial mechanism, not individual clicks. You set the dose dial to your prescribed dose (2.5mg, 5mg, 7.5mg, 10mg, 12.5mg, or 15mg) and inject once weekly. The dial automatically locks once you've injected, preventing accidental re-dosing.
Can I stay on a lower Mounjaro dose instead of titrating to 15mg?
Yes. Your prescriber may recommend staying at 5mg, 10mg, or 12.5mg if you're tolerating it well and achieving good weight loss results. Titration is not mandatory — it's personalised based on your response and side effect tolerance.
What happens if I skip a dose or miss my injection day?
If you miss your injection within 4 days of the scheduled day, inject as soon as you remember and continue your normal schedule. If more than 4 days have passed, skip that dose and inject on your normally scheduled day. Never take a double dose.
Does Mounjaro dose relate to my weight or BMI?
No. Your starting dose is always 2.5mg regardless of your body weight or BMI. Dose increases depend on how you tolerate the medication, side effects, and weight loss progress — not on your starting weight. Everyone follows the same titration schedule.
How does Mounjaro compare to Wegovy for dose progression?
Mounjaro (tirzepatide) starts at 2.5mg and goes up to 15mg. Wegovy (semaglutide) starts at 0.25mg and reaches 2.4mg maximum. Mounjaro is a dual GIP/GLP-1 agonist while Wegovy is GLP-1 only — they have different mechanisms, making dose comparison indirect.
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.