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 to Access Tirzepatide (Zepbound) in the UK
Zepbound is the brand name for tirzepatide, a weekly weight loss injection licensed in the UK for adults with obesity or overweight-related health conditions. Access in the UK depends on whether you choose NHS or private routes, each with different timelines, costs, and eligibility criteria. This guide explains your options and what to expect at each stage.
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.
UK Private Tirzepatide Costs & Prescription Routes
Tirzepatide (Zepbound) cost in the UK through private online prescribing typically ranges from £129 to £320 per month depending on dose and provider. Doses are injected weekly using the KwikPen auto-injector device.
- Starting dose (2.5 mg): approximately £129–£180/month
- Mid-range dose (10 mg): approximately £180–£250/month
- Maximum dose (15 mg): approximately £250–£320/month
Private prescriptions are issued by a UK-licensed prescriber following an online clinical assessment. This GIP receptor and GLP-1 receptor agonist medication can be dispensed by GPhC-registered pharmacies without requiring an NHS referral, making it faster to access than NHS specialist services. Costs vary between providers, so comparing options is recommended before committing.
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 for Tirzepatide in the UK
NHS access: Tirzepatide is available through NHS tier 3/4 specialist weight management services, but access is limited by regional availability and long waiting lists (often 6–18 months). You must be referred by your GP and meet strict eligibility criteria. NICE has approved tirzepatide for NHS use, but availability varies significantly across ICBs.
Private access: Faster route requiring an online consultation with a UK-licensed prescriber. No GP referral needed. Assessment typically takes 24–48 hours. Once approved, your prescription is sent to a registered pharmacy for dispensing. You manage ongoing repeat orders directly with the provider, often with follow-up consultations every 3 months. This weekly weight loss injection option suits those who need prompt access and can self-fund treatment.
- 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 cost of tirzepatide from a private prescriber?
The monthly cost (£129–£320) covers the tirzepatide dose and the KwikPen auto-injector device. It does not include follow-up consultations or ongoing GP monitoring. Some providers offer bundled packages that include regular nurse follow-ups or health checks — check with your provider. Always confirm what's included before ordering.
Can I get tirzepatide (Zepbound) on the NHS in the UK?
Yes, but access is limited. NICE has approved tirzepatide for NHS specialist weight management services. You need a GP referral to tier 3 or 4 weight management services. Eligibility is strict, and waiting lists are long (often 6–18 months or longer). Regional availability varies. Ask your GP about NHS options in your area first.
How long does it take to get tirzepatide through private prescription?
Private online assessment typically takes 24–48 hours. Once approved by a UK-licensed prescriber, your prescription goes to a registered pharmacy for dispensing within 1–2 working days. You could receive your first dose within 3–5 days of starting the process, compared to months of waiting on NHS lists.
Do I need an ongoing prescription from my GP if I use private tirzepatide?
No. Private prescriptions are issued independently by the online prescriber — you don't need GP involvement unless you choose to involve your GP in your care. However, it's good practice to inform your GP that you're taking tirzepatide, as they can monitor your health and help manage any interactions with other medications.
What happens after I've been prescribed tirzepatide — do I need check-ups?
Private providers typically recommend follow-up consultations every 3 months to monitor progress, manage side effects, and adjust your dose if needed. Some providers include this in their service; others charge separately. NHS services include regular specialist monitoring as part of tier 3 care. Always clarify follow-up expectations before starting treatment.
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.