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 Does Mounjaro Cost in the UK?
Mounjaro (tirzepatide) is a prescription-only weight management injection available in the UK through both NHS specialist services and private prescribing routes. The cost varies significantly depending on which pathway you choose — NHS access is free at point of use but involves waiting lists and regional variation, whilst private prescriptions require payment upfront. Understanding your options and eligibility is essential before exploring this treatment. Use our free GLP-1 weight loss calculator to estimate potential outcomes and see if this medication might be right for your goals.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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 Costs and Access in the UK
Private prescriptions in the UK typically cost between £129 and £320 per month depending on the dose you're taking. Mounjaro comes as a KwikPen containing four weekly injections, so costs are usually quoted per month (4-week supply). The starting dose (2.5 mg) is generally the least expensive, whilst higher maintenance doses (10 mg, 15 mg) cost more. You'll need to pay for an online clinical consultation with a UK-licensed prescriber, which typically costs £20–£40. Many private prescribers offer repeat prescription arrangements where you don't need a new consultation for each refill — only periodic check-ins (usually every 3–6 months). Always check whether the quoted price includes the clinical assessment and any follow-up consultations. Private prescriptions are dispensed by GPhC-registered pharmacies and delivered to your home. No NHS referral is required — you can access this route independently.
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 Access vs Private Routes: What You Need to Know
NHS access to Mounjaro is free but requires referral to a specialist tier 3 or tier 4 weight management service — you cannot get it from your GP directly. NICE has approved tirzepatide for NHS use, but availability depends significantly on your region's integrated care board (ICB) funding and capacity. Waiting lists can be many months or even years in some areas. To access NHS treatment, ask your GP to refer you to your local weight management service. Private access is faster but costs money upfront. Complete an online health assessment, receive a prescription if approved, and have medication delivered within days. Using our BMI calculator, you can check your current BMI to understand your eligibility for either route — generally BMI 30+ or 27+ with weight-related health conditions qualify.
- 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's included in the monthly cost of private Mounjaro?
The monthly cost (usually £129–£320) covers the KwikPen containing four weekly doses. Clinical consultation fees (£20–£40) are usually separate, though some providers bundle them. Delivery costs may apply. Always ask for a full price breakdown before purchasing to avoid surprise charges.
Can I get Mounjaro on the NHS for free?
Yes, Mounjaro is available free on the NHS through specialist weight management services, but you must be referred by your GP. NICE has approved it, but availability varies by region and waiting lists can be lengthy. Ask your GP about referral to your local tier 3 service to explore NHS options.
How long does private prescription Mounjaro take to arrive?
After your online consultation is approved (usually within 24–48 hours), your prescription is sent to a pharmacy. Delivery typically takes 3–5 working days. Some providers offer next-day delivery for an additional fee. Always check delivery timescales when choosing a provider.
Is private Mounjaro the same quality as NHS Mounjaro?
Yes. Private prescriptions are dispensed by GPhC-regulated pharmacies and contain the same tirzepatide as NHS supplies — made by Eli Lilly. The only difference is cost and access speed. Quality and efficacy are identical.
Do I need to pay for follow-up appointments with a private prescriber?
Some providers include follow-up check-ins in their service; others charge per consultation (typically £20–£40). Many offer cheaper repeat prescriptions without a full consultation. Clarify the follow-up cost structure before starting treatment, as some ongoing monitoring is recommended.
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.