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 Monthly Subscription — UK Cost & Access Guide
Mounjaro (tirzepatide) is a prescription-only weight management injection available in the UK through both NHS specialist services and private online prescribing. Monthly costs vary significantly depending on the dose and whether you access it through the NHS or privately. Understanding your options — eligibility criteria, pricing, and the prescription process — helps you make an informed decision about whether this medication is right for you. Our GLP-1 weight loss calculator can help you estimate potential outcomes at different doses.
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 Monthly Costs in the UK
Private prescription costs for Mounjaro in the UK typically range from £129 to £320 per month, depending on the dose and private provider. A standard Mounjaro KwikPen contains four weeks of injections — exactly one month's supply.
- Starting dose (2.5 mg): approximately £129–£150 per month
- Mid-range doses (5–10 mg): approximately £180–£240 per month
- Maximum dose (15 mg): approximately £280–£320 per month
Prices vary between GPhC-registered online prescribing services and may change over time. Many providers offer 3-month or 6-month subscription options with modest discounts. A UK-licensed prescriber reviews your medical history and BMI during an online consultation before issuing a prescription — there is no assures of approval. Each KwikPen must be refrigerated and used within 30 days of opening.
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 Monthly Subscription
The NHS does not charge monthly subscription fees — medication is dispensed free through NHS specialist tier 3 weight management services, though waiting times can exceed 6–12 months depending on your region. Private online prescribing bypasses NHS waiting lists but requires you to pay the full monthly cost. To qualify for either route, you typically need a BMI of 30 kg/m² or above, or 27–29.9 with weight-related health conditions such as type 2 diabetes or hypertension. Use our free BMI calculator to check your starting point. The online consultation process takes 10–15 minutes; your prescriber assesses suitability based on your health history, medications, and contraindications before deciding whether to issue a prescription.
- 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 per month on prescription in the UK?
Private Mounjaro costs approximately £129–£320 per month depending on dose, with starting doses around £129–£150 and maximum doses (15 mg) around £280–£320. The NHS provides it free through specialist services, though waiting times vary by region. Prices may vary between providers and change over time.
Can I get Mounjaro free on the NHS?
Yes, Mounjaro is available free through NHS specialist tier 3 weight management services if you meet eligibility criteria (BMI ≥30, or ≥27 with weight-related conditions). However, NHS specialist referral requires a GP referral and can involve waiting lists of several months. Private online prescribing is faster but requires paying the full monthly cost.
Is Mounjaro cheaper than Wegovy?
Costs are similar — both typically range from £129–£320 per month privately depending on dose. Mounjaro may have slightly lower starting dose costs, but this varies between providers. Both require a prescription and clinical assessment. Compare both options with your prescriber based on your individual needs.
What does a Mounjaro KwikPen cost and how long does it last?
A standard KwikPen costs between £129–£320 depending on dose and provider. Each pen contains four weekly injections — exactly one month's supply. After opening, the pen can be stored at room temperature for up to 30 days before it must be discarded, even if medication remains.
Do online Mounjaro prescribers cost extra on top of the medication?
Most GPhC-registered online prescribing services include the prescriber consultation fee within the quoted monthly price (typically £129–£320). Some may charge a separate consultation fee of £20–£50, so check the provider's full pricing before proceeding with an online consultation.
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.