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 to Get Rid of Sulfur Burps on Mounjaro
Sulfur burps (rotten egg-smelling burps) are a reported side effect of Mounjaro (tirzepatide), particularly in the first few weeks of treatment. They're caused by how the medication slows stomach digestion and changes gut bacteria activity. While uncomfortable, they're usually temporary and manageable. This guide explains what causes them, how long they typically last, practical management strategies, and how Mounjaro compares to Wegovy on this specific side effect.
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.
Why Sulfur Burps Happen on Mounjaro vs Wegovy
Sulfur burps occur because Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist that slows gastric emptying — how quickly food moves from your stomach into the small intestine. This slower digestion can lead to fermentation of undigested food in the stomach, which produces hydrogen sulphide gas (the rotten egg smell). The effect is often more pronounced in the first 4–8 weeks as your body adjusts.
Wegovy (semaglutide), by contrast, is a GLP-1-only agonist with a slightly different mechanism. Some users report fewer sulphur burps on Wegovy, though individual experiences vary significantly. Clinical trial data from SURMOUNT (Mounjaro) and STEP (Wegovy) trials did not specifically measure or compare sulphur burps between the two medications, so direct comparison is limited to real-world user reports.
The side effect is not dangerous but can be socially embarrassing and unpleasant. It typically improves or resolves as your digestive system adapts to the medication.
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 Strategies to Reduce or Manage Sulfur Burps
Dietary changes: Eat smaller, more frequent meals rather than large ones. Avoid high-fat, high-fibre, and sulphur-rich foods (eggs, cruciferous vegetables like broccoli and cabbage, garlic, onions, red meat). Stay well hydrated with water.
Digestive support: Ginger tea, peppermint tea, and probiotics may help digestive comfort. Some users report that over-the-counter anti-gas products (simethicone/Infacol) provide temporary relief, though evidence is anecdotal.
Timing: Eat earlier in the day rather than close to bedtime. Allow at least 2–3 hours between eating and lying down.
Physical activity: Gentle movement and walking after meals can support digestion. If side effects persist beyond 8 weeks, contact your prescriber — dose adjustment or medication switch may 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.
How long do sulfur burps last on Mounjaro?
Sulfur burps typically appear in the first 2–4 weeks and often improve or resolve within 4–8 weeks as your body adjusts. Some users experience them for longer, especially if they have existing digestive sensitivities. If they persist beyond 8 weeks, discuss with your prescriber.
Are sulfur burps a sign Mounjaro isn't working?
No. Sulfur burps are a side effect of how Mounjaro slows digestion, not a sign of effectiveness or ineffectiveness. Weight loss and side effects are separate — you can experience both or one without the other.
Do people get sulfur burps on Wegovy instead?
Sulfur burps are less commonly reported with Wegovy (semaglutide), though some users do experience them. Wegovy has a slightly different mechanism as a GLP-1-only agonist, which may reduce this side effect for some people. Individual experiences vary significantly.
Can I stop Mounjaro if sulfur burps are too uncomfortable?
Stopping abruptly is not recommended. If side effects are significantly affecting your quality of life, contact your prescriber. They may adjust your dose, pause treatment temporarily, or discuss switching to an alternative medication like Wegovy after clinical reassessment.
Will changing my diet help reduce sulfur burps on Mounjaro?
Yes. Eating smaller meals, avoiding high-fat and sulphur-rich foods (eggs, cruciferous vegetables), staying hydrated, and eating earlier in the day can reduce burps. Ginger and peppermint tea may also help. These changes support both digestive comfort and weight loss goals.
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.