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 available in the UK through both NHS specialist services and private prescription routes, with costs varying significantly depending on which path you choose. Private prescription prices typically range from £129 to £320 per month, depending on the dose you're prescribed. The NHS route is free at point of care but involves waiting lists and specialist referral requirements. Understanding your options helps you make an informed decision about which access route suits your circumstances and budget.
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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 Costs in the UK
Private prescription costs for Mounjaro in the UK typically range from approximately £129–£320 per month, with prices varying based on the dose prescribed. A Mounjaro KwikPen contains four weekly injections (one month's supply). Each dose increment—from 2.5 mg through to the maximum 15 mg—carries a different cost, with higher doses generally commanding higher prices. Initial consultation fees are usually additional, ranging from £20–£50 depending on the provider. Some private prescribers offer package deals that reduce per-month costs if you commit to longer treatment periods. It's important to note that tirzepatide (the active ingredient) is the same across all UK providers—price differences reflect service delivery, platform quality, and clinical support rather than product quality. Always verify that any provider is registered with the GPhC (General Pharmaceutical Council) and offers proper clinical assessment.
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 Prescription
NHS access to Mounjaro is free but requires referral to a tier 3 or 4 specialist weight management service—your GP can refer you, though waiting lists vary significantly by region and can extend several months to over a year in some areas. NICE approved tirzepatide for NHS use, but availability depends on your local Integrated Care Board (ICB) commissioning decisions and specialist service capacity. Private prescription routes offer faster access without NHS referral; you complete an online clinical assessment with a UK-licensed prescriber who decides eligibility based on your health profile. If approved, your prescription is dispensed by a GPhC-registered pharmacy and posted to you. The private route costs more but eliminates waiting lists and gives you immediate access. Many people use our free GLP-1 weight loss calculator to estimate potential outcomes before committing to 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.
Why does Mounjaro cost more privately than some other weight loss injections?
Mounjaro's pricing reflects its dual GIP and GLP-1 mechanism, brand positioning, and manufacturer costs. Clinical trial data showed tirzepatide produced slightly higher average weight loss than single-mechanism GLP-1 medications. Private prescribers also factor in consultation time, clinical assessment, ongoing support, and prescription delivery. Not all providers charge the same—compare services, not just price.
Can I get Mounjaro on the NHS without waiting?
NHS waiting times vary dramatically by region. Some areas have waiting lists of 6–12 months; others may be longer or shorter depending on local service capacity and commissioning. Your GP can tell you your local tier 3 service waiting time. If speed is essential, private prescription offers faster access but at personal cost.
What's included in the monthly Mounjaro cost?
A monthly cost typically covers one Mounjaro KwikPen (four weekly injections at your prescribed dose) and delivery to your home. Consultation fees are usually separate. Some private providers include follow-up clinical checks; others charge additionally. Always clarify what's included before committing.
Is there a cheaper alternative to Mounjaro in the UK?
Wegovy (semaglutide) is another licensed weight loss injection with similar private pricing (typically £100–£250/month depending on dose). Saxenda (liraglutide) is also available but costs more and requires daily injections instead of weekly. NHS access may be cheaper or free but involves waiting and specialist referral. Use our free BMI calculator to confirm eligibility before exploring options.
Do I need a fresh prescription each month for Mounjaro?
That depends on your provider. Some online prescribers issue repeat prescriptions for 3–6 months if your clinical situation remains stable, reducing repeat consultation fees. Others require monthly reassessment. Ask your prescriber about their repeat prescription policy—this can affect your total monthly cost and convenience.
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.