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
Maintaining on Mounjaro in the UK — Cost and Access
Once you've reached your target maintenance dose of Mounjaro (tirzepatide), you'll continue taking the same weekly injection unless your prescriber recommends otherwise. The cost of maintenance depends entirely on whether you're accessing Mounjaro through the NHS or privately in the UK. This guide explains both routes, what ongoing prescriptions involve, and realistic costs for staying on your maintenance dose long-term.
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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 Mounjaro Maintenance Cost in the UK
Private prescription costs for Mounjaro maintenance vary depending on the dose you're on and which provider you use. At 15 mg (the maximum maintenance dose), expect to pay approximately £130–£180 per month, though prices vary between GPhC-registered online pharmacies. Lower maintenance doses (5 mg or 10 mg) typically cost less — around £100–£140 monthly. Each KwikPen contains four weeks' supply of a single dose. Unlike NHS services, private providers do not conduct extensive follow-up monitoring — you'll receive your prescription following an online clinical assessment, and repeat prescriptions usually require a brief check-in every 3–6 months. Some private services offer subscription models with discounts for regular repeat orders. Always verify the pharmacy is GPhC-registered before paying.
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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 Access for Mounjaro Maintenance
NHS access: If you've been prescribed Mounjaro through a tier 3 specialist weight management service, you continue receiving it free on the NHS for as long as your prescriber deems it appropriate. However, NHS access varies significantly by region — some integrated care boards (ICBs) have more generous provision than others. Waiting times to access NHS specialist services can be very long (months to years in some areas), which is why many people choose private access. Private access: Available without NHS referral through an online consultation with a UK-licensed prescriber. The clinical assessment checks your BMI, medical history, and suitability. If approved, your prescription is dispensed by a GPhC-registered pharmacy and delivered to your home. Repeat prescriptions are straightforward — contact the provider when you're due for your next dose.
- 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 often do I need to see a doctor if I'm on Mounjaro maintenance privately?
Most private providers require a brief online check-in every 3–6 months to ensure the medication is still appropriate. You won't have the same level of monitoring as NHS services, so it's important to track your own progress using our free progress tracker and report any concerning side effects to your prescriber.
Can I switch from NHS to private Mounjaro, or vice versa?
Yes, you can switch. If you're on NHS Mounjaro and want to go private, you'll need a new private prescription (NHS prescriptions aren't transferable to private pharmacies). If you're private and want NHS access, you'd need to be referred to an NHS tier 3 service, though this can be a lengthy process depending on your area.
Does the cost of Mounjaro maintenance include GP monitoring?
Private prescription costs do not include GP monitoring — they cover the medication and online prescriber assessment only. Your own GP can monitor your health, but they won't be involved in prescribing or managing your Mounjaro dose. NHS Mounjaro includes full specialist monitoring as part of the service.
What happens to the cost if I need to increase my dose during maintenance?
If your prescriber recommends increasing from your current maintenance dose, you'll typically pay more per month once you move to the higher dose. For example, moving from 10 mg to 15 mg may increase your monthly cost by £30–£50 depending on your provider. Always clarify costs before dose changes.
How much does an initial online consultation cost for a private Mounjaro prescription?
Initial consultations through private providers typically cost £0–£50, though some offer free assessments. Check with your chosen provider. The prescription itself (the medication cost in COL_H) is separate from the consultation fee. Many providers bundle the consultation cost into your first month's supply.
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.