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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Easiest Place To Get Mounjaro In The UK
Finding the easiest place to get Mounjaro in the UK depends on whether you choose NHS or private access. The NHS route involves referral to specialist tier 3 weight management services, which can involve waiting lists. Private access is faster — through GPhC-registered online pharmacies following an online clinical assessment. Both routes require a prescription from a UK-licensed prescriber and an assessment of your eligibility based on BMI and health factors. Understanding your options helps you choose the route that fits your circumstances.
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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.
NHS Vs Private Access Routes — Key Differences
The two main routes to access Mounjaro (tirzepatide) in the UK are NHS specialist services and private online prescribing. NHS access: Requires GP referral to a tier 3 or tier 4 specialist weight management service. These services are free but availability varies significantly by region and waiting lists can be several months to over a year in many areas. Once assessed and approved, you receive your Mounjaro KwikPen prescriptions through the NHS at no cost. Private access: Faster route — complete an online clinical consultation with a UK-licensed prescriber, typically receiving a decision within 24–48 hours. If approved, your prescription is dispensed by a GPhC-registered pharmacy. Costs range from approximately £129–£320 per month depending on dose, with no waiting list. Both routes require you to meet NHS weight loss injection UK eligibility criteria: BMI of 30 or above, or 27–29.9 with a weight-related health condition.
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.
Mounjaro Vs Wegovy — Which Is Easier To Access?
Both Mounjaro vs Wegovy follow the same access pathways in the UK — NHS or private — so access difficulty is roughly equal. The practical difference is in the mechanism and dosing. Mounjaro is a dual GIP and GLP-1 receptor agonist with dose titration from 2.5 mg up to 15 mg maximum, whilst Wegovy is a single GLP-1 agonist with lower maximum dose of 2.4 mg. Clinical trial data from SURMOUNT (Mounjaro) showed approximately 15–21% average body weight loss, whilst STEP trials (Wegovy) showed around 15%. Individual results vary significantly. Your prescriber will assess which is more suitable based on your health profile and preferences. Both require a clinical assessment before prescription, whether through NHS specialist services or private consultations.
- 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.
Is it faster to get Mounjaro through the NHS or private in the UK?
Private access is significantly faster. Private consultations typically receive a prescriber decision within 24–48 hours, whilst NHS specialist services often have waiting lists of several months to over a year depending on your region. Both routes are legitimate; the choice depends on your timeline and budget.
What's the difference between Mounjaro and Wegovy for UK weight loss?
Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist reaching 15 mg maximum dose. Wegovy (semaglutide) is a single GLP-1 agonist with 2.4 mg maximum dose. Both are once-weekly injections licensed in the UK. Clinical trial data suggests similar average weight loss outcomes, though individual results vary. Your prescriber will assess which suits you better.
Do I need a GP referral to get Mounjaro privately in the UK?
No. Private online prescribing does not require a GP referral. You complete an online clinical assessment with a UK-licensed prescriber directly. However, if you choose the NHS route, you need a GP referral to a specialist tier 3 weight management service. Your GP can provide this referral based on your health needs.
What's the cost of Mounjaro on prescription in the UK?
Through the NHS, Mounjaro is free at point of use once prescribed by a specialist service. Privately, costs range from approximately £129–£320 per month depending on your dose (2.5 mg through 15 mg). Prices vary between providers. Your prescriber will discuss costs before you proceed.
How quickly will I lose weight on Mounjaro?
Weight loss timelines vary individually. Clinical trials (SURMOUNT) showed average weight loss of 15–21% of body weight over 72 weeks at maximum dose, alongside a reduced-calorie diet and physical activity. Many people notice reduced appetite within the first few weeks. Use our free GLP-1 weight loss calculator to estimate potential outcomes based on your starting weight and dose.
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.