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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Wegovy for Diabetes in the UK
Wegovy (semaglutide) is a GLP-1 receptor agonist that helps with weight management and can improve blood sugar control. In the UK, Wegovy is licensed for weight management in adults with a BMI of 30 or above, or 27 or above with weight-related health conditions — including type 2 diabetes or prediabetes. If you have diabetes and excess weight, your GP or specialist can assess whether Wegovy might be suitable for you. This guide explains NHS eligibility, how it works, and your options for access.
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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.
NHS Eligibility and How Wegovy Works for Diabetes
Wegovy is a once-weekly injectable GLP-1 medication that activates receptors in the brain and gut to reduce appetite and support blood sugar regulation. For people with type 2 diabetes or prediabetes, weight loss is a key part of managing blood sugar levels — Wegovy addresses both.
NHS eligibility for Wegovy includes:
- Adults aged 18+ with a BMI of 30 kg/m² or above
- Adults with BMI of 27–29.9 kg/m² AND a weight-related health condition (including type 2 diabetes, prediabetes, high blood pressure, or cardiovascular disease)
- South Asian, Chinese, Black African, or Black Caribbean adults may qualify at lower BMI thresholds (from 27.5 kg/m²)
The STEP clinical trial showed that people taking semaglutide 2.4 mg lost an average of approximately 15% of their body weight over 68 weeks alongside a reduced-calorie diet and increased physical activity. Individual results vary, and weight loss alone can significantly improve type 2 diabetes management.
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 Wegovy in the UK
NHS route: Wegovy is available through tier 3 specialist weight management services. You will need a referral from your GP, and availability varies significantly by region. Some areas have waiting lists of several months. Your diabetes clinic may refer you directly if weight management is a priority for your care.
Private route: Wegovy is available through UK-licensed online prescribers following a clinical assessment. This avoids NHS waiting lists but requires payment. Costs typically range from £129–£250 per month depending on your dose. Either route requires a valid prescription from a UK-licensed prescriber — no medication is dispensed without clinical assessment. Use our free GLP-1 weight loss calculator to explore potential outcomes, and the BMI calculator to check your current category.
- 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.
Can I get Wegovy on the NHS if I have type 2 diabetes?
Yes, if you meet eligibility criteria. You must have a BMI of 30 or above, or BMI of 27–29.9 with type 2 diabetes (which counts as a weight-related health condition). Access is through tier 3 specialist weight management services via GP referral. NHS availability varies by region and waiting lists can be long.
How does Wegovy help with diabetes?
Wegovy (semaglutide) is a GLP-1 receptor agonist that reduces appetite, helps you feel fuller, and slows gastric emptying. It also helps regulate blood sugar response. Weight loss itself — even 5–10% — can significantly improve type 2 diabetes control and reduce medication need.
What's the difference between Wegovy and Ozempic for diabetes?
Both contain semaglutide, but Ozempic is licensed for type 2 diabetes management (up to 2 mg dose). Wegovy is licensed specifically for weight management (up to 2.4 mg dose). Using Ozempic for weight loss is off-label in the UK. Wegovy is the appropriate choice if weight management is your primary goal.
What dose of Wegovy would I start on?
Wegovy starts at 0.25 mg once weekly for the first 4 weeks, then escalates gradually: 0.5 mg (weeks 5–8), 1 mg (weeks 9–12), 1.7 mg (weeks 13–16), and 2.4 mg (week 17 onwards). Your prescriber will adjust based on how you tolerate the medication.
Are there side effects I should know about?
Common side effects include nausea, diarrhoea, constipation, and stomach pain — particularly when starting or increasing doses. These typically reduce over time. More serious but rare side effects include severe stomach pain (possible pancreatitis) and gallbladder problems. Always report any concerning symptoms to your GP or prescriber.
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.