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 Half Dose Clicks — Cost & Access in the UK
A "half dose click" of Mounjaro refers to the 2.5mg starter dose, which is the lowest available strength of tirzepatide available on the Mounjaro KwikPen. This is the standard starting dose for adults beginning weight management treatment in the UK. Whether you access Mounjaro privately or through the NHS, understanding the cost, eligibility, and prescription process helps you make an informed decision about this treatment option.
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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.
UK Private Mounjaro Cost and Availability
In the UK, Mounjaro (tirzepatide) is available privately through online prescribing services following a clinical assessment. Private cost for the 2.5mg starter dose typically ranges from £129 to £180 per KwikPen, with each pen containing four weekly injections (a month's supply). Prices vary depending on the prescribing service and whether you're assessed as eligible for treatment.
The 2.5mg starting dose is designed to be tolerated well, with side effects often minimal at this strength. Most users remain on this dose for 4 weeks before escalating to the 5mg dose. Private access via UK-licensed prescribers means you don't need an NHS referral — you can access treatment more quickly, though you'll pay out of pocket. Compare this to the GLP-1 alternative Wegovy, which starts at a lower dose (0.25mg) and typically costs similarly at equivalent strengths.
- Price: approximately £129–£180 per pen (4 weeks supply)
- Eligibility: BMI ≥30, or BMI 27–29.9 with weight-related health condition
- Timeline: prescription within days, not months
- Prescriber assessment required before dispensing
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 Routes and What to Expect
NHS route: Available through specialist tier 3 weight management services after GP referral, but availability varies significantly by region. Waiting lists can extend months to years. Once approved, Mounjaro is provided free on the NHS, but you'll follow the NHS escalation protocol.
Private route: Faster access (days to weeks) via online consultation with a UK-licensed prescriber. You'll complete a health questionnaire, receive a clinical assessment, and if approved, your prescription is sent to a GPhC-registered pharmacy. Use our GLP-1 weight loss calculator to estimate potential outcomes at different doses, and our BMI calculator to confirm your eligibility based on current weight and height. Private treatment gives you flexibility in dosing and prescriber choice, though cost is your responsibility.
- 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.
What exactly is a "half dose click" of Mounjaro?
The 2.5mg dose is the starter dose — the lowest strength on the Mounjaro KwikPen. Each click on the pen represents one weekly injection. The term "half dose click" sometimes refers to this starting strength relative to standard maintenance doses (5mg and above), though it's actually a full starter dose, not literally half.
How much does Mounjaro 2.5mg cost privately in the UK?
Private Mounjaro 2.5mg costs roughly £129–£180 per KwikPen (4-week supply) depending on the prescribing service. This is an estimate; prices vary. Always confirm the exact price with the prescriber before committing to treatment.
Can I get Mounjaro on the NHS for weight management?
Yes, Mounjaro is now available via NHS specialist weight management services (tier 3) in some areas. However, availability and waiting times vary significantly by region. Ask your GP about referral to your local specialist service. Private access is often faster if you're willing to pay.
How long do I stay on the 2.5mg starting dose?
Standard protocol is to remain on 2.5mg for 4 weeks before escalating to the 5mg dose, provided you're tolerating it well. Your prescriber may adjust this timeline based on your response and any side effects. Dose titration is gradual to minimise nausea and digestive symptoms.
Is Mounjaro the same as Wegovy, and do they cost the same?
No — Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist, while Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials showed Mounjaro produced slightly higher average weight loss, though results vary individually. Costs are broadly similar at equivalent stages of treatment, but always compare quotes.
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.