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
Prednisone and Weight Loss โ What You Need to Know
Prednisone (a corticosteroid) typically causes weight gain rather than weight loss, but some people report weight loss during or after treatment. Understanding how prednisone affects your metabolism and appetite, and knowing your weight management options in the UK, can help you take control of your health. If you've noticed changes in your weight while taking prednisone, your GP can offer personalised guidance and explore appropriate support strategies.
10,000+ calculations today ยท NHS-aligned thresholds ยท 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/mยฒ).
While BMI isn't a perfect measure โ it doesn't account for muscle mass, bone density, or fat distribution โ 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 โ 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.
How Prednisone Affects Weight and Metabolism
Prednisone typically increases appetite and causes water retention, leading to weight gain in most patients. However, the relationship between steroids and weight is complex. Some people experience weight loss when prednisone is tapered down, as appetite-stimulating effects subside and fluid retention decreases. Others find their metabolism changes significantly, making it harder to maintain their previous weight even when reducing the dose.
- Prednisone increases cortisol levels, boosting appetite and promoting fat storage around the abdomen
- Water and sodium retention can account for 2โ5kg of apparent weight gain
- Individual metabolism varies โ some people gain more weight than others on the same dose
- Weight changes often reverse gradually after stopping prednisone, though this can take months
- Higher doses and longer treatment courses tend to cause more significant weight changes
If you're taking prednisone and concerned about your weight, discuss with your GP whether dose adjustments or tapering schedules are possible, and explore weight management strategies that work alongside your medication.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care โ 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 โ 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 โ completely free.
Weight Management Options When Taking Prednisone
Managing weight while on prednisone requires a practical approach that acknowledges the medication's metabolic effects. Focus on balanced nutrition, adequate protein intake, and regular physical activity โ even gentle exercise helps preserve muscle mass. Limiting sodium can reduce fluid retention, and staying hydrated supports overall health. Your GP may refer you to a tier 1 NHS weight loss programme or community weight management service for support.
When prednisone treatment ends, sustainable weight loss through diet and exercise typically follows naturally as hormonal effects normalise. If you need additional support, prescription weight management options โ including GLP-1 weight loss injections โ are available through NHS specialist services or private assessment. Use our free BMI calculator to track your weight status, and try our progress tracker to monitor changes over time as your treatment progresses.
- 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 โ 5mg โ 7.5mg โ 10mg โ 12.5mg โ 15mg
- GLP-1 receptor agonist
- Up to 15โ17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg โ 0.5mg โ 1mg โ 1.7mg โ 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 | 15โ22.5% | 12โ17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20โ32 weeks | 16โ20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | ยฃ150โยฃ250/month | ยฃ150โยฃ300/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 โ 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.
Does prednisone cause weight loss?
Prednisone typically causes weight gain, not loss, due to increased appetite and fluid retention. However, some people experience weight loss when the dose is reduced or stopped, as medication effects diminish. Weight changes vary significantly between individuals. Always discuss changes with your GP.
Why does prednisone make you gain weight?
Prednisone increases cortisol levels, which boosts appetite and promotes fat storage (especially around the abdomen). It also causes sodium and water retention. These effects are temporary and usually reverse after treatment ends, though recovery takes time.
How long does prednisone weight gain take to come off?
Weight loss after stopping prednisone happens gradually, typically over weeks to months. Water weight often reduces quickly once the dose decreases, but fat loss requires sustained diet and exercise. Your GP can advise on realistic timescales based on your individual situation.
Can I lose weight while still taking prednisone?
Yes, weight loss is possible but challenging because prednisone increases appetite. Focus on balanced nutrition, regular activity, and reducing sodium to minimise fluid retention. Your GP can refer you to an NHS weight management programme for structured support alongside your medication.
Are weight loss injections an option after prednisone treatment?
If you've experienced persistent weight gain after prednisone treatment, prescription weight loss options โ including GLP-1 weight loss injections โ may be available through NHS specialist services or private prescription. Eligibility depends on your BMI and health factors. Your GP can assess whether this option is 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.