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
Does Mounjaro Stop You Drinking Alcohol?
Mounjaro (tirzepatide) does not directly stop you from drinking alcohol, but it may affect how your body tolerates it. The medication can cause nausea and stomach discomfort, which alcohol may worsen. There is no absolute ban on alcohol whilst taking Mounjaro, but moderation is recommended. Your GP or prescriber should discuss this during your clinical assessment, as individual responses vary based on your health and the dose you are taking.
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 Mounjaro Affects Alcohol Tolerance
Mounjaro is a dual GIP and GLP-1 receptor agonist injection used for weight management in the UK. Whilst there is no pharmacological interaction between tirzepatide and alcohol itself, the medication can make certain side effects worse when combined with alcohol.
- Nausea: Mounjaro frequently causes nausea, especially in the first weeks or when dose titration occurs. Alcohol is a stomach irritant and may intensify this side effect.
- Dehydration: Both alcohol and Mounjaro can contribute to dehydration, potentially increasing dizziness or fatigue.
- Blood sugar effects: If you have prediabetes or type 2 diabetes, alcohol can unpredictably affect blood glucose levels, and Mounjaro also influences glucose regulation.
- Pancreatitis risk: Very rarely, both alcohol and GLP-1 medications have been linked to pancreatitis — combining them increases theoretical risk.
Your prescriber will advise on your specific situation based on your health history and the KwikPen dose you are using.
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.
Practical Guidance for Alcohol Whilst on Mounjaro
If you choose to drink alcohol whilst on Mounjaro, moderation is key. This means up to 14 units per week for women and men according to UK health guidance. Drink slowly, eat food beforehand, and stay hydrated with water. Avoid binge drinking and monitor how you feel — nausea, dizziness, or stomach pain should prompt you to stop and speak to your GP.
Discuss your specific alcohol use with your prescriber during your clinical assessment. They can advise based on your health conditions, other medications you take, and your Mounjaro eligibility. Some people find alcohol tolerance decreases on the injection, so start with less than you might normally drink.
- 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.
Can I drink alcohol on Mounjaro at all?
There is no absolute ban on alcohol whilst taking Mounjaro, but moderation is strongly recommended. Alcohol may worsen nausea and stomach discomfort caused by the medication. Always discuss your alcohol consumption with your prescriber before starting treatment.
Does Mounjaro interact with alcohol like some other medications?
Mounjaro does not have a direct pharmacological interaction with alcohol, but the combination can amplify side effects such as nausea, dehydration, and dizziness. Individual responses vary, so your prescriber should assess your personal risk.
Will alcohol affect how well Mounjaro works for weight loss?
Alcohol is high in calories and may impact your weight loss results indirectly by adding calories to your diet. However, moderate alcohol consumption will not reduce Mounjaro's mechanism of action. Your overall calorie intake and physical activity remain the primary factors.
What if I experience severe nausea when mixing Mounjaro and alcohol?
If you experience severe nausea, vomiting, or stomach pain after drinking alcohol on Mounjaro, stop drinking immediately, stay hydrated, and contact your GP. These could indicate a more serious issue, though rarely this combination may indicate pancreatitis in severe cases.
Is my Mounjaro NHS prescription or private?
In the UK, Mounjaro is available through NHS tier 3 specialist weight management services (where access and waiting lists vary significantly by region) or through private online prescribing via GPhC-registered pharmacies. Your prescriber route affects how you access alcohol guidance — always ask at your clinical assessment.
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.