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
Is Wegovy Good For Weight Loss in the UK?
Wegovy is a prescription-only weekly weight loss injection that has shown promising results in clinical trials, but cost and access are important considerations for UK adults. This guide explains how effective Wegovy is, what it costs in the UK, and how to access it through NHS or private routes. Whether Wegovy is right for you depends on your eligibility, health needs, and budget — so we'll help you understand all the options.
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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.
Wegovy Cost and Access in the UK
Private prescription cost: Wegovy through private UK online prescribing services typically costs between £149–£280 per month depending on your dose. This includes the prescription assessment, medication, and delivery. You do not need an NHS referral — just an online consultation with a UK-licensed prescriber.
NHS access: The NHS does fund Wegovy through specialist tier 3 weight management services, but availability varies dramatically by region. Many areas have significant waiting lists (sometimes 12–24 months), and not all integrated care boards (ICBs) currently fund it. You'll need a GP referral to access NHS specialist services.
- Starting dose (0.25 mg) costs less than maximum dose (2.4 mg)
- Private costs can add up over time — monthly treatment could exceed £3,000 per year
- NHS access is free at point of use but often limited by availability
- GLP-1 injections like Wegovy are not available through standard GP prescription — only through specialist pathways
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.
How to Access Wegovy: NHS vs Private Route
NHS route: Ask your GP for a referral to your local tier 3 specialist weight management service. They'll assess your eligibility (BMI 30+, or 27+ with weight-related health conditions) and may prescribe Wegovy if appropriate. However, waiting lists are long and funding varies by area — check with your ICB directly about current availability.
Private route: Complete an online consultation with a UK-licensed prescriber through a GPhC-registered pharmacy. Answer health questions, receive assessment within 24–48 hours, and if approved, receive your prescription and weekly injection pens by post. No NHS referral needed. Start within days rather than months.
Whichever route you choose, use our free GLP-1 weight loss calculator to understand potential results, and track your progress with our weight loss tracker once you start 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.
How much weight can you lose with Wegovy?
Clinical trials showed Wegovy users lost an average of approximately 15% of their body weight over 68 weeks at the maximum dose (2.4 mg), alongside a reduced-calorie diet and physical activity. Individual results vary significantly — some people lose more, some less. Use our GLP-1 weight loss calculator to estimate your potential weight loss based on your starting weight.
Is Wegovy available on the NHS in the UK?
Yes, Wegovy is NHS-funded through specialist tier 3 weight management services, but availability is extremely limited. Waiting lists can exceed 12 months in many areas, and some ICBs do not currently commission it. Ask your GP about referral options in your region. Private prescription is faster but costs £150–£280 monthly.
What is the difference between Wegovy and Mounjaro?
Both are once-weekly weight loss injections, but they work differently. Wegovy (semaglutide) is a GLP-1 agonist, while Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist. Clinical trials suggest Mounjaro may produce slightly higher average weight loss, but both are effective. Eligibility and cost differ — your prescriber will advise which suits you.
What are the main side effects of Wegovy?
Common side effects include nausea, diarrhoea, constipation, and stomach pain — particularly when starting or increasing doses. Most side effects settle within a few weeks. Serious side effects are rare but include severe stomach pain (possible pancreatitis) and gallbladder problems. Always report persistent symptoms to your prescriber. See our Wegovy side effects guide for full details.
Do I need a GP's permission to get Wegovy privately?
No. Private Wegovy prescriptions do not require NHS involvement. You complete an online assessment with a UK-licensed prescriber, who decides whether it's safe for you based on your medical history. However, if you have existing health conditions, tell your GP that you're considering GLP-1 treatment so they can monitor your care alongside private prescribing.
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.