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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Peri Menopause Weight Loss: UK Medication Options
Weight gain during peri menopause is common due to hormonal changes, but prescription weight management options are now available in the UK for eligible adults. This guide explains the licensed medications that may help with weight loss during this life stage, who can access them through the NHS or privately, and how to have a conversation with your GP about what might work for you.
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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.
UK-Licensed Prescription Weight Loss Options
Three prescription-only weight loss medications are licensed in the UK and may be appropriate during peri menopause: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). These are GLP-1 or dual GIP/GLP-1 receptor agonist medications that help reduce appetite and support feeling fuller after smaller meals.
In clinical trials, these medications helped adults lose an average of 15–21% of their body weight when combined with dietary changes and increased physical activity. Results vary significantly between individuals. Eligibility typically requires a BMI of 30 kg/m² or above, or a BMI of 27–29.9 kg/m² with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea — conditions that may be more common during peri menopause.
All three are injections: Mounjaro and Wegovy are once-weekly, while Saxenda is a daily injection. A prescriber will assess whether any of these options is suitable for your individual health before dispensing.
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 Access vs Private Options
NHS access: Weight loss medications are available through specialist tier 3 weight management services, typically accessed via GP referral. However, NHS availability varies significantly by region, and waiting lists can be lengthy in many areas.
Private access: These medications are also available through GPhC-registered online prescribing services following an online clinical assessment. Private treatment does not require an NHS referral and is often more readily available, though it involves out-of-pocket costs starting around £129–£320 per month depending on dose.
Either route requires a clinical assessment to confirm eligibility. Our GLP-1 weight loss calculator can help you understand potential weight loss outcomes at different doses, and you can use our BMI calculator to check whether you fall within typical eligibility ranges. Speaking with your GP is always a good starting point — they can advise on NHS options in your area and discuss whether prescription weight loss treatment is appropriate for you.
- 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.
Why is weight gain common during peri menopause?
Hormonal fluctuations — particularly declining oestrogen levels — slow metabolism, increase appetite, and promote fat storage around the abdomen. Sleep disruption, reduced physical activity, and increased stress during peri menopause can also contribute. Weight gain during this life stage is physiological, not a personal failure.
Am I eligible for prescription weight loss medication during peri menopause?
Eligibility depends on BMI and health status, not on menopausal status specifically. If your BMI is 30 or above, or 27–29.9 with weight-related conditions like high blood pressure or sleep apnoea, you may be eligible. Your GP or a licensed prescriber can assess your individual circumstances.
Can I use prescription weight loss medication alongside HRT?
Yes, these medications can be used alongside HRT. However, GLP-1 medications may reduce absorption of oral medications, including some hormone therapies. Always inform your prescriber of all medications and supplements you are taking so they can advise on timing or adjustments.
How quickly will I lose weight on these medications?
Clinical trials showed average weight loss of 15–21% over 68–72 weeks when combined with diet and exercise. Individual results vary. Most people see gradual changes over weeks to months. Your prescriber will monitor progress and adjust your dose if needed.
What if I don't want to try medication — are there other options?
Yes. NHS Tier 1 services include digital tools, community programmes, and behavioural support. Mediterranean diet, intermittent fasting, and structured exercise are evidence-based approaches. Our BMI calculator and progress tracker can help you monitor progress with any approach you choose. Your GP can discuss all options with 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.