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 Weight Plateau: UK Access and Cost Guide
A weight plateau on Mounjaro is common and doesn't mean the medication has stopped working — your body may simply be adjusting to a new stable weight. If you're considering or already using this weekly weight loss injection in the UK, understanding how to access it and what costs are involved can help you make informed decisions. Whether you're exploring NHS options or private prescription routes, this guide covers the realistic costs and access pathways available to UK adults.
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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.
Private Mounjaro Access and Typical UK Costs
Private prescription access: In the UK, Mounjaro is available through GPhC-registered online pharmacies following a clinical assessment with a UK-licensed prescriber. You don't need an NHS referral — the process is typically faster than NHS specialist services. Costs vary significantly depending on the dose and provider, generally ranging from approximately £129 to £320 per month for different dose levels.
- 2.5 mg starting dose: typically £129–£160/month
- 5–10 mg maintenance doses: £180–£240/month
- 15 mg maximum dose: £260–£320/month
Each KwikPen contains four weekly doses (one month's supply). Some providers offer discount packages if you commit to multiple months. Costs do not include the clinical consultation fee, which is usually £25–£50. Try our GLP-1 weight loss calculator to estimate potential outcomes at different doses, helping you weigh the financial investment against projected results.
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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 Routes: What's Available Now
NHS access: NICE has approved tirzepatide (Mounjaro) for use within NHS specialist weight management services. However, NHS prescription is limited to tier 3 or tier 4 specialist weight management services — you cannot get it from your GP directly. Access requires referral from your GP and assessment by a specialist team. Waiting times vary dramatically by region, with some areas reporting waits of 12+ months.
Private route advantages: Faster access, no waiting list, assessment based on clinical need rather than regional availability. Private route trade-off: you pay the full cost yourself. Both routes require confirmation that you meet eligibility criteria: BMI of 30 or above, or 27 or above with weight-related health conditions such as type 2 diabetes or high blood pressure.
Online consultation process: After registering with a private provider, you complete a health questionnaire covering medical history, current medications, and weight loss goals. A UK prescriber reviews this and may approve a prescription if you're clinically suitable. The entire process typically takes 24–48 hours. Once approved, your prescription is sent to a GPhC pharmacy for dispensing — you receive your KwikPen by post within 2–5 working days. Track your progress using our free progress tracker to monitor weight changes and help you assess whether dose adjustments might be needed during your treatment journey.
- 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 in the UK each month?
Private costs typically range from £129–£320 per month depending on dose. Starter doses (2.5 mg) cost around £129–£160, mid-range doses (5–10 mg) cost £180–£240, and the maximum dose (15 mg) costs £260–£320. These costs do not include the clinical consultation fee, usually £25–£50. Prices vary between providers.
Can I get Mounjaro free on the NHS in the UK?
Yes, NICE has approved tirzepatide for NHS weight management services. However, access is through specialist tier 3/4 services, not your GP. You need a referral and assessment by a specialist team. Availability and waiting times vary significantly by region — some areas have waits of many months. Private prescription is typically faster if you're willing to pay.
What is a weight plateau on Mounjaro and is it permanent?
A weight plateau is when your weight stabilises and stops decreasing despite being on the medication and following a reduced-calorie diet. It's not permanent — it often indicates your body has reached a new stable weight. Your GP or prescriber may recommend dose escalation, dietary adjustment, or increased physical activity. Plateaus are normal and don't mean Mounjaro has stopped working.
What happens if I want to switch from Mounjaro to Wegovy?
Both are prescription-only medications requiring a prescriber's decision. There's no official conversion chart, though rough equivalences exist (for example, Mounjaro 10 mg is roughly equivalent to Wegovy 1.7 mg). Any switch must be managed by your prescriber. You'll need to stop one medication and start the other — never switch without clinical guidance.
Do online prescribers check if Mounjaro is suitable for me?
Yes. UK-licensed prescribers conduct a clinical assessment via a health questionnaire. They review your medical history, current medications, weight, height, and any weight-related health conditions. They assess whether you meet eligibility criteria (BMI 30+ or 27+ with comorbidities) and whether the medication is safe for you. This assessment is thorough but conducted online — not face-to-face.
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.