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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Mounjaro and Social Impact in the UK
Weight loss medication like Mounjaro (tirzepatide) has significant implications for UK health equity, NHS resources, and how society approaches weight management. As a prescription-only medicine approved by NICE for eligible adults, access to Mounjaro raises important questions about who can access treatment, regional variation in NHS prescribing, and the broader social context of obesity. Understanding these social and health system impacts helps you make informed decisions about your own health and treatment options.
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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 Access, Eligibility, and Health Inequality
Mounjaro eligibility in the UK is determined by strict NICE-approved criteria: adults with a BMI of 30 kg/m² or above, or BMI of 27–29.9 kg/m² with weight-related health conditions such as type 2 diabetes, cardiovascular disease, or obstructive sleep apnoea. However, access is not equal across the UK. Specialist tier 3 weight management services—where Mounjaro is typically prescribed on the NHS—vary significantly by region. Some ICBs (Integrated Care Boards) have long waiting lists or limited availability, while others offer faster access. This creates geographical health inequality: your postcode can determine how quickly you can access treatment. Private prescribing has grown as a result, making Mounjaro available to those who can pay privately, typically £200–£320 monthly depending on dose titration and the tirzepatide dose (ranging from 2.5 mg up to the maximum 15 mg once weekly). This dual-access model raises concerns about equitable healthcare.
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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.
Social and Economic Impact of Weight Loss Treatment
Mounjaro's availability has changed social and economic dynamics around weight management in the UK. Unlike previous approaches relying primarily on diet and exercise, prescription medications offer a medical option for people who struggle with sustained weight loss. Clinically, Mounjaro clinical trials showed average weight loss of 15–21% body weight at different doses—results that can significantly improve health outcomes and reduce burden on NHS services. However, cost and access disparities mean treatment is not equally available. Public health experts raise concerns about creating a two-tier system where affluent individuals access the latest medications whilst others wait months for NHS tier 3 referrals. Additionally, media coverage and social media have increased public awareness and demand, sometimes outpacing NHS capacity. The broader social impact includes shifting perceptions of obesity from purely a behavioural issue to a treatable medical condition—a positive change in stigma—balanced against concerns about medication dependency and long-term outcomes.
- 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.
Who can access Mounjaro on the NHS in the UK?
Adults with a BMI of 30 kg/m² or above, or 27–29.9 kg/m² with weight-related health conditions like type 2 diabetes or cardiovascular disease, may be eligible through NHS specialist tier 3 weight management services. Eligibility is assessed individually. Lower BMI thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults due to higher health risks at lower weights.
Why is there a waiting list for Mounjaro on the NHS?
NHS specialist weight management services face significant demand. Tier 3 services have limited capacity, and many regions have waiting lists of several months. Private prescribing has expanded to meet demand from people unable to access NHS services quickly. Your GP can advise on local waiting times and whether private options are appropriate for you.
What is the difference between NHS and private Mounjaro prescribing in the UK?
NHS prescribing is through specialist tier 3 services following a GP referral and clinical assessment—it's free but involves waiting lists. Private prescribing is through online prescribers and GPhC-registered pharmacies—faster but costs £200–£320 monthly. Both routes require a prescription and clinical assessment; both are equally valid pathways to treatment.
Does Mounjaro reduce pressure on the NHS long-term?
Yes, potentially. Weight loss reduces the incidence of type 2 diabetes, cardiovascular disease, and other conditions that cost the NHS billions annually. However, this benefit only materialises if treatment is sustained and access is equitable. Short-term NHS costs may be offset by long-term savings if widespread access reduces obesity-related disease burden.
How does Mounjaro compare to Wegovy in terms of NHS access?
Both Mounjaro and Wegovy are prescription-only and available through NHS tier 3 services or private prescribing. NICE has approved both for weight management in the UK. Availability and waiting times vary by region and service. Your GP or a licensed prescriber can advise which option is more appropriate for your individual circumstances.
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.