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
How Much Is Monjaro in the UK — Cost & Access
Monjaro (tirzepatide) is a prescription-only weight loss injection available in the UK through both NHS specialist services and private online prescribing. The cost varies significantly depending on whether you access it through the NHS or privately. Private prescription costs typically range from £130 to £320 per month depending on your dose, while NHS access is free at point of care but involves waiting times and regional availability. Understanding your options helps you make an informed decision about accessing this GLP-1 receptor agonist medication.
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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.
Monjaro Cost Through Private UK Prescribing
Private Monjaro (tirzepatide) costs in the UK typically range from £130 to £320 per month, depending on which dose you're prescribed. Each KwikPen contains four weekly doses, so costs reflect the full month's supply. Starting doses (2.5 mg) are usually at the lower end of this range, while higher maintenance doses (10 mg and above) cost more. Costs may also vary slightly between different GPhC-registered online pharmacies. Private access requires an online clinical assessment with a UK-licensed prescriber, who will determine if Monjaro is suitable for you based on your BMI, health conditions, and medical history. You can use our free GLP-1 weight loss calculator to see projected results at different doses before making a decision. Payment is typically required upfront, though some providers offer subscription options that may provide modest savings over time. Private prescriptions bypass NHS waiting lists, making treatment immediately available if you meet eligibility criteria.
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 — What's the Difference?
NHS route: Free at point of care but requires GP referral to a tier 3 specialist weight management service. Waiting lists vary dramatically by region—some areas have waits of 6–12 months or longer. NICE has approved tirzepatide for NHS use, but availability depends on your local Integrated Care Board (ICB) budget and policies. Private route: Costs £130–£320/month but offers immediate access without referral. You consult a UK-licensed prescriber online, receive a prescription if eligible, and obtain medication from a GPhC-registered pharmacy. No NHS waiting list. Both routes require you to have a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or high blood pressure. Check your personal BMI using our free BMI calculator to confirm eligibility before pursuing either route.
- 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 Monjaro free on the NHS?
Yes, Monjaro is free at point of care through the NHS, but you must be referred to a specialist tier 3 weight management service by your GP. The main cost is time—waiting lists can be lengthy depending on your region. Private access costs £130–£320/month but offers immediate treatment without NHS waiting times.
How much does a Monjaro KwikPen cost privately?
A single KwikPen, containing four weekly doses, typically costs £130–£320 depending on the dose strength and the pharmacy. Starting doses cost less than higher maintenance doses. Prices may vary slightly between GPhC-registered online prescribing services.
Can I get Monjaro cheaper with a subscription?
Some private online prescribing services offer subscription or repeat prescription options that may reduce the per-month cost slightly. These typically work out cheaper than one-off purchases if you plan to continue treatment long-term. Compare options when choosing a provider.
What happens after I get a Monjaro prescription?
Once prescribed, you'll receive your KwikPen from a GPhC-registered pharmacy, either collected or delivered. You inject once weekly at home using the pre-filled pen. Your prescriber may ask you to check in after a few weeks to see how you're getting on and whether dose adjustments are needed.
Do I need to pay for blood tests or GP consultations with Monjaro?
Private online consultations are typically charged as part of the overall service cost (included in the £130–£320 price or charged separately—check before committing). NHS Monjaro includes any necessary monitoring through your specialist service at no extra cost, though you may wait longer for appointments.
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.