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
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Can Mounjaro Cause Vertigo and Dizziness?
Yes, dizziness and vertigo are known side effects of Mounjaro (tirzepatide), though they are relatively uncommon. Dizziness appears in clinical trial data as a side effect affecting a small proportion of users, particularly during the initial weeks of treatment or when your dose is increased. Understanding whether Mounjaro might cause vertigo, and how to access it safely in the UK, helps you make an informed decision about this prescription-only weight management injection. If dizziness is a concern for you, your GP or prescriber can assess your individual situation and recommend the best approach.
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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.
Mounjaro Side Effects: Vertigo, Dizziness, and Access in the UK
Dizziness and vertigo are reported side effects of Mounjaro during clinical trials, though they occur in a small percentage of users. Vertigo specifically — a sensation that you or your surroundings are spinning — is less common than general dizziness. Dizziness typically appears early in treatment or when your dose increases, and often improves as your body adjusts. Other common Mounjaro side effects include nausea, vomiting, constipation, and stomach pain. More serious but rare side effects include pancreatitis (severe stomach pain) and gallbladder issues. The Mounjaro KwikPen delivery system itself does not cause vertigo, but the medication's effects on your digestive system and appetite regulation may contribute to dizziness in some people. If you experience persistent vertigo while taking Mounjaro, contact your prescriber immediately — they may adjust your dose or suggest alternative management strategies. Always report any new or worsening symptoms to your healthcare provider.
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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.
Accessing Mounjaro in the UK: NHS vs Private Cost and Routes
In the UK, Mounjaro is available through two main routes: NHS specialist weight management services and private prescription. NHS access requires referral from your GP to a tier 3 or 4 weight management clinic; availability and waiting times vary significantly by region and ICB. Private prescription involves an online consultation with a UK-licensed prescriber, typically costing £129–£320 per month depending on your dose. Once prescribed, a GPhC-registered pharmacy dispenses your Mounjaro KwikPen. Eligibility for both routes requires a BMI of 30 or above, or 27–29.9 with weight-related health conditions such as type 2 diabetes or high blood pressure. Your prescriber will assess whether tirzepatide is appropriate for you, considering your medical history and any side effect concerns like dizziness. Private routes mean faster access without NHS waiting lists, though cost is a factor to consider.
- 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 vertigo a common side effect of Mounjaro?
Dizziness is reported in clinical trials, but true vertigo (spinning sensation) is relatively uncommon. Most users do not experience it, though it may occur during the first few weeks or when doses increase. Symptoms often settle as your body adjusts to the medication.
What should I do if I experience dizziness on Mounjaro?
Contact your prescriber or GP immediately, especially if dizziness is severe or persistent. They may adjust your dose, recommend taking Mounjaro at a different time, or suggest temporary lifestyle changes. Do not drive if you feel dizzy. Your prescriber can advise whether continuing Mounjaro is appropriate for you.
How much does Mounjaro cost privately in the UK?
Private Mounjaro typically costs between £129 and £320 per month, depending on your dose level. The starting dose (2.5mg) costs less than higher maintenance doses (15mg). Prices vary between private prescribing services, so comparing options before consultation is worthwhile.
Can I access Mounjaro through the NHS instead of paying privately?
Yes, Mounjaro is available on the NHS through specialist tier 3 weight management services. However, you must be referred by your GP, and waiting times can be lengthy (often several months). NHS access depends on your regional ICB's commissioning decisions and local service capacity.
What's the difference between Mounjaro and Wegovy for side effects like dizziness?
Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist, whilst Wegovy (semaglutide) is a GLP-1 agonist only. Both can cause dizziness, though side effect profiles are slightly different. Your prescriber can help determine which is more suitable based on your health history and tolerance to medication side effects.
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.