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
Staying on 5mg Mounjaro — When and Why
Some people remain on 5mg Mounjaro long-term and see sustained results, while others escalate to higher doses for greater weight loss. Whether staying on 5mg is right for you depends on your individual health, weight loss goals, and how you tolerate the medication. In the UK, tirzepatide (Mounjaro) is prescribed through NHS specialist weight management services or private online prescribing, with dose decisions guided by your prescriber. This guide explains the NHS context, eligibility criteria, and what to expect if you continue at the 5mg maintenance dose.
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.
5mg Mounjaro in NHS Context — Dose and Efficacy
5mg is the first maintenance dose in the standard Mounjaro titration schedule. According to the SURMOUNT clinical trials, participants on 5mg saw an average weight loss of approximately 15% of their body weight over 72 weeks — achieved alongside a reduced-calorie diet and increased physical activity. This is a significant result, though individual responses vary considerably.
In NHS specialist tier 3 weight management services, your prescriber will assess whether continuing at 5mg is appropriate based on:
- Your weight loss progress so far
- How well you tolerate the medication
- Your individual health goals and risk factors
- Any side effects you're experiencing
- Your engagement with diet and exercise changes
Some people achieve their target weight and maintain it at 5mg. Others continue to escalate through 7.5mg, 10mg, 12.5mg, and up to the maximum 15mg dose if needed. There is no universal "right" dose — it's personalised to you.
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 at 5mg vs. Increasing — What You Should Know
If you're considering staying at 5mg rather than increasing, discuss this clearly with your prescriber. Weight loss plateaus are normal — your body adapts to medication over time. A dose increase may help, but staying at 5mg may also be effective if you adjust your diet and exercise further, or if you're satisfied with your progress so far.
On a UK Mounjaro KwikPen, 5mg is delivered once weekly. After 4 weeks at this dose, your prescriber can discuss whether to increase or maintain. Important: never change your dose without guidance from your prescriber. If you're accessing Mounjaro through NHS services, your prescriber will review you regularly. If through private prescribing, ensure you have scheduled follow-up appointments to monitor progress and safety.
Use our free GLP-1 weight loss calculator to estimate potential weight loss across different Mounjaro doses and see how 5mg compares to higher doses. Additionally, our BMI calculator helps you track how your BMI changes as weight comes off, giving you context for your progress against NHS healthy weight guidelines.
- 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 5mg Mounjaro a permanent dose?
No — 5mg is typically a maintenance dose within the titration schedule, but your prescriber may recommend continuing at this level if you're achieving your goals and tolerating it well, or increasing further if weight loss plateaus. This is reviewed regularly with your prescriber.
Can I stay on 5mg Mounjaro forever?
Yes, if your prescriber agrees it's appropriate and you're achieving sustained weight loss and health benefits. However, long-term studies are ongoing, and regular monitoring with your healthcare provider is essential. Your prescriber will advise on duration based on your individual situation.
What's the average weight loss at 5mg Mounjaro in the UK?
Clinical trials (SURMOUNT-1) showed participants lost an average of approximately 15% of their body weight at 5mg over 72 weeks, alongside lifestyle changes. Individual results vary significantly — some lose more, some less, depending on genetics, adherence, and diet.
Should I increase from 5mg Mounjaro if I've hit a weight loss plateau?
A plateau after several weeks is normal as your body adapts. Your prescriber may recommend increasing your dose, or optimising your diet and exercise further before escalating. Never change your dose without consulting your prescriber — they'll assess whether an increase is right for you.
How do I access Mounjaro at 5mg on the NHS in the UK?
NHS access is through tier 3 specialist weight management services — ask your GP for a referral. Availability and waiting times vary significantly by region (ICB). Private online prescribing via GPhC-registered pharmacies is also available without an NHS referral if you meet eligibility criteria.
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.