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
Weight Loss and Blood Pressure — UK Prescription Options
Losing weight can significantly help reduce high blood pressure, and the NHS recognises this link as part of weight management for health. If you're overweight and struggling with hypertension, prescription weight loss medication may be an option for you in the UK. This guide explains how weight loss affects blood pressure, which medications are available, and how to find out if you're eligible through the NHS or private prescribing routes.
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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.
UK-Licensed Weight Loss Medications for Blood Pressure Management
Three prescription-only weight management injections are licensed in the UK and may help adults with excess weight and weight-related health conditions like high blood pressure:
- Mounjaro (tirzepatide) — a once-weekly dual GIP and GLP-1 receptor agonist. Clinical trials showed average weight loss of 15–21% of body weight alongside reduced-calorie diet and physical activity.
- Wegovy (semaglutide) — a once-weekly GLP-1 receptor agonist. Clinical evidence demonstrated approximately 15% average body weight reduction in trials.
- Saxenda (liraglutide) — a once-daily GLP-1 injection, typically prescribed as a starter option.
All three work by reducing appetite, helping you feel fuller after smaller meals, and supporting sustainable weight loss. Individual results vary, and these medications are always used alongside lifestyle changes—diet and physical activity remain essential.
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 — How to Get Started
On the NHS: Weight loss medication is prescribed through specialist tier 3 weight management services. You'll need a GP referral and assessment by the specialist team. Availability and waiting times vary significantly by region (integrated care board), and some areas have lengthy waiting lists.
Privately: Prescription weight loss medication is available through GPhC-registered online pharmacies following an online clinical assessment with a UK-licensed prescriber. You don't need an NHS referral. To find out if you're eligible—on the NHS or privately—your GP or a licensed prescriber will assess your BMI, health conditions, and medical history. Use our free BMI calculator to check your starting point, and discuss weight management options at your next GP appointment.
- 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 loss is needed to lower blood pressure?
Even a 5–10% reduction in body weight can meaningfully lower blood pressure in many people. The NHS emphasises that sustainable weight loss of 0.5–1 kg per week, achieved through both dietary changes and increased physical activity, produces the best long-term results for blood pressure control.
Am I eligible for prescription weight loss medication in the UK?
Eligibility depends on BMI and health conditions. Adults with a BMI of 30 or above, or 27–29.9 with weight-related conditions like high blood pressure, may be eligible. Your GP or a licensed prescriber will assess your individual circumstances. Use our GLP-1 weight loss calculator to explore potential outcomes.
Can I use weight loss injections while taking blood pressure medication?
Weight loss medications may interact with some blood pressure medicines, and gradual weight management can change medication requirements. Your prescriber and GP must know all your current medications. Never stop or adjust blood pressure medication without medical guidance—your GP will monitor and adjust as you lose weight.
What's the difference between Mounjaro and Wegovy for blood pressure?
Both are prescription-only, once-weekly injections. Mounjaro uses a dual mechanism (GIP + GLP-1), while Wegovy is GLP-1 only. Clinical trials show both support significant weight loss. Your prescriber will recommend the most suitable option based on your health profile and eligibility.
How long does it take to see blood pressure improvements?
Blood pressure often begins to improve within weeks of starting weight loss, even before significant weight loss is achieved. Consistent weight loss over months typically produces the most stable reductions. Regular monitoring by your GP helps track progress and adjust any medications as needed.
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.