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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How Can I Get Mounjaro in the UK?
Mounjaro (tirzepatide) is a prescription-only weight management injection available in the UK through two main routes: the NHS and private prescribing services. Access depends on your eligibility, which is based on BMI and weight-related health conditions. This guide explains both pathways, what the prescription process involves, and how long you might expect to wait. Whether you're considering NHS access or exploring private options, understanding your choices is the first step.
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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 Access to Mounjaro
In the UK, Mounjaro is available through the NHS, but access is restricted to specialist tier 3 and tier 4 weight management services. You cannot get it from your GP directly — you need a referral.
- First step: Speak to your GP about weight management support. They will assess your eligibility based on BMI (30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes, hypertension, or sleep apnoea) and may refer you to your local specialist weight management service.
- Regional variation: Access differs significantly across England, Scotland, Wales, and Northern Ireland. Some ICBs (Integrated Care Boards) offer Mounjaro; others may only offer alternatives like Saxenda or lifestyle programmes.
- Waiting times: NHS specialist services often have lengthy waiting lists — in some areas, months or even years. NICE approved tirzepatide for NHS use, but availability remains inconsistent.
- Specialist assessment: Once referred, you'll be assessed by a weight management team who will decide if Mounjaro is appropriate for you and determine your starting dose.
Check your local NHS trust or ICB website to understand Mounjaro availability in your area.
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.
Private Access to Mounjaro
Private prescribing offers faster access without NHS referral. You can obtain Mounjaro through GPhC-registered online pharmacies following an online clinical consultation with a UK-licensed prescriber.
- Complete an online health questionnaire assessing your medical history, medications, and weight loss goals.
- A prescriber reviews your information and decides if Mounjaro is suitable. If approved, they issue a prescription.
- The prescription is dispensed by a regulated pharmacy and delivered to your home.
- Costs typically range from £129 to £320+ per month depending on your dose and provider.
- Private prescribing is regulated but requires you to manage your own clinical follow-up — GPs may or may not support private weight loss medication use.
Private access is faster but requires you to pay and take responsibility for ongoing dose management and side effect monitoring.
- 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.
What BMI do I need to get Mounjaro?
You are eligible if your BMI is 30 or above, or 27–29.9 with at least one weight-related health condition (type 2 diabetes, prediabetes, high blood pressure, abnormal blood fats, sleep apnoea, or cardiovascular disease). Use our free BMI calculator above to check your personal BMI and health context.
How long does the NHS prescription process take?
There is no standard timeline. You first need a GP referral to specialist services, which can take weeks or months. Then waiting lists for specialist assessment vary from weeks to over a year depending on your region. Private prescribing is typically much faster — often 24–48 hours from consultation to delivery.
Can my GP prescribe Mounjaro directly?
No. Mounjaro is only prescribed through NHS specialist tier 3/4 weight management services, not standard GP practice. You must be referred by your GP to these specialist services first. Private prescribing bypasses this, but requires an online consultation with an independent prescriber.
Is Mounjaro the same as Wegovy or Ozempic?
No. Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist — different from Wegovy (semaglutide, GLP-1 only). Ozempic also contains semaglutide but is approved for diabetes, not weight loss. All three are prescription-only, but Mounjaro and Wegovy are specifically licensed for weight management in the UK.
Will my private Mounjaro prescription be supported by my NHS GP?
Not automatically. Some GPs will monitor you while using privately obtained weight loss medication; others won't. Before starting private treatment, contact your GP practice to ask if they will support shared care and help monitor your health. This affects how you manage side effects and dose changes.
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.