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
Do I Have To Increase My Mounjaro Dose?
No, you do not have to increase your Mounjaro dose if it's working well for you. Dose increases are optional and based on your individual response to treatment. Your prescriber will assess your progress at each stage and discuss whether stepping up to the next dose is right for you. Some people reach their weight loss goals at lower doses, whilst others may benefit from titration to higher doses. The key is finding what works for your body and health goals.
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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.
How Mounjaro Dose Titration Works in the UK
Mounjaro (tirzepatide) comes in a standard dose titration schedule that starts at 2.5 mg and increases weekly over several weeks, reaching a maximum of 15 mg. However, titration is not mandatory—your prescriber will tailor your treatment plan based on your individual response, weight loss progress, and tolerance of side effects. You'll typically spend at least 4 weeks on each dose before considering an increase. If you're experiencing significant appetite reduction, sustainable weight loss, and managing side effects well at a lower dose, your prescriber may recommend staying at that level rather than escalating. Conversely, if you're not seeing meaningful progress and tolerating the medication well, stepping up may be discussed. Your prescriber will review your progress regularly and adjust your Mounjaro UK prescription accordingly, ensuring you receive the most effective dose for your circumstances.
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 Dose Decisions and Private vs NHS Access
Whether you increase your Mounjaro dose depends on several factors: your weight loss progress, how well you tolerate side effects, your health goals, and your prescriber's clinical judgment. Private online prescribers will assess your progress via follow-up consultations (usually monthly) and recommend dose adjustments based on your feedback. NHS specialist services follow NICE guidance and typically review patients at regular intervals to determine if titration is appropriate. Neither route forces you to increase—both prioritise finding your optimal dose. If you're using our GLP-1 weight loss calculator, you can explore projected outcomes at different doses to discuss with your prescriber. Cost may also influence decisions; discussing dose goals upfront during your initial online consultation helps establish a personalised treatment plan that matches both your health needs and your circumstances.
- 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's the difference between staying on one Mounjaro dose versus titrating up?
Staying on one dose keeps your treatment stable if it's working well—many people achieve significant weight loss at 5 mg or 10 mg. Titrating up may increase appetite suppression and weight loss potential but also increases side effect risk. Your prescriber helps you decide based on your progress and tolerance.
If I'm losing weight on 5 mg Mounjaro, do I need to go up to 10 mg?
No. If you're seeing good progress and managing side effects well at 5 mg, there's no clinical reason to increase. Dose escalation is optional and individualised. Stay on the dose that achieves your goals with manageable side effects.
How does Mounjaro compare to Wegovy in terms of dose increases?
Both involve dose titration schedules. Mounjaro goes up to 15 mg weekly; Wegovy reaches 2.4 mg weekly. Neither requires automatic escalation. Your prescriber assesses your response and recommends increases only if clinically appropriate and well-tolerated.
What happens if I want to stay on a lower Mounjaro dose long-term?
This is perfectly reasonable if you're achieving your weight loss goals and managing side effects. Discuss your preference with your prescriber during consultations. They'll support a stable lower dose if it's working for you, versus escalating if progress stalls.
Does the cost of Mounjaro in the UK change with different doses?
Yes, generally higher doses cost more on private prescriptions. Discuss dose goals and associated costs during your initial online consultation. NHS access through specialist services removes private cost barriers, though availability varies by region.
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.