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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Cycling Weight Loss — UK Prescription Options
If you're cycling regularly but struggling with weight loss, prescription medication may support your efforts alongside exercise and diet. The UK has several licensed weight management options available through NHS specialist services or private prescription. Understanding what's available and whether you're eligible is the first step. This guide covers the prescription medications approved in the UK, who can access them, and how to start a conversation with your GP about weight management 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.
UK-Licensed Weight Loss Medications
Three prescription medications are currently licensed in the UK for weight management in adults:
- Mounjaro (tirzepatide) — A dual GIP and GLP-1 receptor agonist, injected once weekly. Clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks, though individual results vary significantly.
- Wegovy (semaglutide) — A GLP-1 receptor agonist, injected once weekly. Average weight loss in trials was approximately 15% of body weight, alongside reduced-calorie diet and increased physical activity.
- Saxenda (liraglutide) — A GLP-1 receptor agonist, injected daily. The oldest of the three licensed options.
All three are prescription-only medicines requiring clinical assessment before prescription. Eligibility typically includes adults with a BMI of 30 or above, or BMI 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or cardiovascular disease. Your GP or prescriber will assess whether medication is suitable for you based on your individual health profile and goals.
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 in the UK
In the UK, you can access prescription weight loss medication through two routes:
- NHS route: Referral to tier 3 specialist weight management services via your GP. This is free but availability varies significantly by region and waiting times can be lengthy in many areas.
- Private route: Online consultation with a UK-licensed prescriber followed by dispensing through a GPhC-registered pharmacy. Available without NHS referral, though there is a cost (typically £129–£320 per month depending on medication and dose).
Whichever route you choose, weight loss medication works best alongside lifestyle changes. Your GP can discuss which approach suits your circumstances, and you can use tools like our free BMI calculator and GLP-1 weight loss calculator to understand your starting point and potential outcomes before initiating 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.
Can cycling alone help me lose weight without medication?
Yes — regular cycling burns calories and can contribute to weight loss, especially when combined with a calorie deficit through diet. However, some people find that medication alongside exercise and dietary changes helps accelerate progress, particularly if previous attempts have been unsuccessful. Your GP can advise whether medication might help in your case.
Who is eligible for weight loss medication in the UK?
Generally, adults with a BMI of 30 or above, or 25–29.9 with weight-related conditions like type 2 diabetes or high blood pressure. Some ethnic groups (South Asian, Black African, Black Caribbean, Chinese) may be eligible at lower BMI thresholds due to higher health risks. A prescriber will assess your individual eligibility.
How long does it take to see weight loss results with these medications?
Most people notice changes within the first few weeks, though significant weight loss typically develops over several months. Clinical trials measured results at 68–72 weeks. Results vary between individuals and depend on dose, diet, exercise, and personal factors.
Are weight loss injections safe to use while cycling?
For most people, yes — but it's important to discuss your exercise routine with your prescriber when starting medication. They may advise staying hydrated and monitoring your energy levels, particularly when increasing doses. Any concerns should be discussed with your GP.
What's the difference between Mounjaro and Wegovy?
Both are once-weekly injections, but Mounjaro (tirzepatide) activates two hormone pathways (GIP and GLP-1), while Wegovy (semaglutide) activates one (GLP-1). Clinical trials suggest slightly higher average weight loss with Mounjaro, but individual responses vary. Your prescriber will recommend which is more appropriate for you.
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.