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
What Is Mojaro? UK Health Guide
Mojaro is a prescription-only weight management injection licensed in the UK for adults with excess weight. It's the brand name for tirzepatide, a dual GLP-1 and GIP receptor agonist that works differently from other weight loss medications. This UK health guide explains how Mojaro works, who may be eligible, and how to access it through NHS specialist services or private prescribing. Whether you're exploring weight management options or researching healthy weight UK solutions, understanding how Mojaro fits into the NHS guidance framework is an important first step.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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.
How Mojaro Works and Key Facts
Mojaro (tirzepatide) is a once-weekly injection that activates two natural hormone pathways: GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1). This dual mechanism is what sets it apart from single-action GLP-1 medications. It may help reduce appetite, support feeling fuller after meals, and slow how quickly food leaves the stomach — though this effect typically reduces over time.
- Prescription-only medicine — requires a prescription and clinical assessment
- Doses range from 2.5 mg to 15 mg, increased weekly over several weeks
- Each pen contains a 4-week supply (four doses)
- Clinical trials showed average weight loss of 15–21% of body weight when combined with reduced-calorie diet and increased physical activity
- Individual results vary significantly — weight loss is not assured
Try our free GLP-1 weight loss calculator to estimate potential outcomes at different doses, or use our BMI calculator to check if you may meet eligibility criteria.
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.
UK Eligibility and How to Access Mojaro
In the UK, adults with a BMI of 30 or above, or BMI of 27–29.9 with weight-related health conditions may be eligible for Mojaro. Weight-related conditions include type 2 diabetes, prediabetes, high blood pressure, abnormal blood fats, sleep apnoea, or previous heart attack or stroke. South Asian, Chinese, Black African, and Black Caribbean adults may have lower eligibility thresholds due to higher cardiovascular risk at lower BMI levels — check with your GP or healthcare provider about your individual eligibility.
Access routes: NHS access is through tier 3 specialist weight management services (often requiring GP referral and with significant waiting lists in many areas). Private access is available through GPhC-registered online pharmacies following a clinical assessment by a UK-licensed prescriber. Use our weight converter and BMI calculator to understand where you currently stand against NHS healthy weight UK thresholds.
- 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 Mojaro the same as Ozempic or Wegovy?
No. Mojaro, Ozempic, and Wegovy all contain different medications. Mojaro contains tirzepatide (dual GIP+GLP-1 agonist). Ozempic contains semaglutide but is licensed only for type 2 diabetes, not weight loss. Wegovy also contains semaglutide but at a higher dose and is licensed specifically for weight management. Each works slightly differently and requires its own prescription.
How much weight can I expect to lose on Mojaro?
Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks when combined with diet and exercise changes. However, individual results vary significantly — some people lose more, some less. Weight loss is not assured. Results depend on your starting weight, adherence to medication, dietary changes, physical activity, and individual metabolism.
Can I get Mojaro on the NHS in the UK?
Possibly. NICE has approved tirzepatide (Mojaro) for NHS specialist weight management services. However, access requires referral to a tier 3 service through your GP, and availability and waiting times vary significantly by region. Many areas have long waiting lists. Private access is available without NHS referral through online prescribing services.
What are the main side effects of Mojaro?
Very common side effects include nausea, diarrhoea, vomiting, constipation, and stomach pain — usually mild and temporary. Common side effects include indigestion, headache, fatigue, and dizziness. Serious side effects are rare but may include severe stomach pain (possible pancreatitis) or allergic reactions. Discuss all side effects with your prescriber.
Is Mojaro suitable during pregnancy or whilst breastfeeding?
No. Mojaro is not suitable if you're pregnant, planning pregnancy, or breastfeeding. Women taking oral contraceptives should use additional barrier contraception for 4 weeks after starting Mojaro and 4 weeks after each dose increase, as Mojaro may reduce oral medication absorption. Discuss contraception with your prescriber.
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.