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
Getting Mounjaro Through an Online Pharmacy in the UK
Mounjaro (tirzepatide) is available through UK-registered online pharmacies, but only with a valid prescription from a licensed prescriber. Unlike over-the-counter products, you cannot buy Mounjaro without a clinical assessment. This guide explains how the online prescription pathway works, eligibility criteria, and what to expect when accessing this weight management medication through private channels in the UK. Always ensure any online pharmacy is GPhC-registered for your safety.
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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.
How Online Mounjaro Prescriptions Work in the UK
To obtain Mounjaro through an online pharmacy in the UK, you must first complete an online clinical assessment with a UK-licensed prescriber. The prescriber will review your medical history, current medications, weight, height, and BMI to determine if Mounjaro is appropriate for you. If approved, they issue a prescription which is sent directly to a GPhC-registered pharmacy for dispensing.
The tirzepatide KwikPen (Mounjaro's delivery device) is then posted to your address. The entire process typically takes 3–7 working days from assessment to delivery, depending on the provider. Key point: this is not a shortcut to medication—the clinical assessment is mandatory, not optional. Prescribers have professional and legal responsibility to ensure suitability before issuing a prescription.
You'll receive guidance on injection technique, storage (refrigerated at 2–8°C), and how to rotate injection sites (stomach, thigh, or upper arm). Many providers also offer follow-up support via phone or messaging.
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.
Eligibility and What Prescribers Assess
UK prescribers will assess whether you meet eligibility criteria before approving Mounjaro. You typically need a BMI of 30 or above, or BMI of 27–29.9 with at least one weight-related health condition (type 2 diabetes, prediabetes, high blood pressure, high cholesterol, sleep apnoea, or cardiovascular disease history). For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds may apply due to higher health risks at these weights.
Prescribers will also check for contraindications: you cannot use Mounjaro if you're pregnant, breastfeeding, under 18, have a severe allergy to tirzepatide, or have certain stomach conditions. Your GP doesn't need to be involved—this is a private assessment pathway. Use our free BMI calculator above to check your personal BMI before applying, and our GLP-1 weight loss calculator to see potential outcomes at different doses.
Cost and NHS alternative: Online prescriptions for Mounjaro are private and not funded by the NHS. Prices vary by provider and dose, typically ranging from £129–£320 per month depending on which dose strength you're prescribed. The starting dose is 2.5 mg (increasing weekly) up to a maximum of 15 mg. Compare this to NHS access: you can also request an NHS referral to a specialist tier 3 weight management service through your GP, though waiting lists in many areas are very long. Some people choose private access for speed and convenience.
Always verify the online pharmacy is registered with the GPhC (General Pharmaceutical Council). Check their registration on the GPhC website before providing payment or personal information. Reputable providers are transparent about prescriber qualifications, costs, and privacy policies.
- 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 Mounjaro available without a prescription from online pharmacies in the UK?
No. Mounjaro is prescription-only in the UK and cannot be legally sold without a valid prescription from a licensed prescriber. Any online pharmacy claiming to sell Mounjaro without a prescription is operating illegally. Always require a clinical assessment and prescription as proof of legitimacy.
How is Mounjaro prescribed online different from getting it on the NHS?
Online private prescribing is faster (usually 3–7 days) and doesn't require NHS referral or GP involvement. NHS access is free but involves waiting lists and often requires referral to specialist services. Both require a clinical assessment—the difference is speed, convenience, and cost. Private online costs £129–£320/month; NHS is free but availability varies by region.
What's the difference between Mounjaro and Wegovy if I'm looking online?
Mounjaro (tirzepatide) is a dual GIP + GLP-1 receptor agonist with a starting dose of 2.5 mg, maximum 15 mg weekly. Wegovy (semaglutide) is a GLP-1 agonist only, starting at 0.25 mg, maximum 2.4 mg weekly. Clinical trials showed Mounjaro achieved approximately 20.9% average weight loss at maximum dose versus 14.9% for Wegovy—though individual results vary significantly. Both are available through UK online pharmacies.
What should I check before using an online pharmacy for Mounjaro?
Verify the pharmacy is GPhC-registered by checking the General Pharmaceutical Council website. Confirm the prescriber is UK-licensed. Check privacy and data protection policies. Read reviews from verified customers where possible. Reputable providers are transparent about costs, delivery times, and follow-up support. Never pay upfront without seeing prescriber qualifications or privacy information first.
Can my GP refuse to support me if I'm taking Mounjaro prescribed privately online?
Your GP cannot refuse ongoing care, though some practices may be reluctant to monitor privately prescribed weight loss medications. It's best to inform your GP you're taking Mounjaro so they can monitor for any interactions with other medications and track health improvements (blood pressure, blood sugar, cholesterol). Keep records of your prescription and doses to share with your GP if needed.
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.