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
How Often Do You Take A Mounjaro Maintenance Dose?
Mounjaro (tirzepatide) is taken as a once-weekly injection, and this frequency remains the same during the maintenance phase. After you've reached your target maintenance dose—typically between 5 mg and 15 mg—you continue injecting once every seven days for as long as your GP or prescriber recommends. The maintenance dose itself doesn't change how often you inject; rather, it's the dose amount that stays steady once you've completed the dose titration schedule. Understanding this schedule is important for planning your treatment and tracking progress with our free BMI calculator and GLP-1 weight loss calculator.
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.
Mounjaro vs Wegovy: Maintenance Dosing Comparison
Both Mounjaro (tirzepatide) and Wegovy (semaglutide) follow a once-weekly injection schedule, including the maintenance phase. The key difference lies in the dose amounts and titration speed:
- Mounjaro: Starts at 2.5 mg, escalates every 4 weeks through 5 mg, 7.5 mg, 10 mg, 12.5 mg, and up to 15 mg maintenance
- Wegovy: Starts at 0.25 mg, escalates over 16+ weeks to a maximum maintenance dose of 2.4 mg
In clinical trials, the SURMOUNT-1 study (Mounjaro) and STEP-1 study (Wegovy) both demonstrated weight loss outcomes with once-weekly dosing. Individual results vary significantly, and your prescriber will determine which medication and dose is suitable based on your personal health assessment. Your choice of medication—and maintenance dose—depends on individual suitability, not on injection frequency.
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.
Staying on Mounjaro Maintenance: What to Expect
Once you reach your maintenance dose of Mounjaro, the injections continue at the same frequency (once per week) and dose amount unless your prescriber adjusts them. You do not need to keep escalating—the dose remains stable. Some people stay on their maintenance dose long-term; others may adjust if they experience side effects or if their health needs change. You'll typically have regular check-ins with your GP or prescriber to monitor how you're responding. Track your progress with our free progress tracker, and use our BMI calculator to monitor any changes in your weight or BMI. If you experience persistent side effects, speak to your prescriber about whether a dose adjustment or switch to another medication might be appropriate.
- 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 maintenance dose once a week?
Yes. Mounjaro is a once-weekly injection at all stages, including maintenance. After reaching your target maintenance dose (typically 5–15 mg), you continue injecting once every seven days. The injection frequency does not change—only the dose amount may be adjusted by your prescriber if needed.
How long do you stay on Mounjaro maintenance dose?
Duration varies by individual. Some people remain on their maintenance dose long-term for ongoing weight management; others may adjust or stop based on their health goals and prescriber guidance. Your GP or prescriber will review your progress regularly and discuss the best approach for you.
What is the difference between Mounjaro and Wegovy dosing?
Both are once-weekly injections, but Mounjaro reaches higher maximum doses (up to 15 mg) compared to Wegovy (up to 2.4 mg). Mounjaro is a dual GIP+GLP-1 agonist, while Wegovy is a GLP-1 agonist only. Clinical trial data shows both can support weight loss, though individual results vary significantly.
Can you skip a Mounjaro maintenance injection?
No. Skipping doses may reduce effectiveness and can affect your weight management progress. If you miss a dose by more than 4 days, skip that week and resume your normal schedule. If you have concerns about your treatment plan, discuss them with your prescriber rather than adjusting doses yourself.
Is Mounjaro available on the NHS for maintenance treatment?
Mounjaro is available through NHS specialist tier 3/4 weight management services following clinical assessment. Access varies significantly by region and availability. Private prescription is also available through UK-licensed prescribers following an online clinical assessment. Your GP can discuss which route is suitable for you.
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.