Smelly Burps on Mounjaro: What Causes Them and What to Do

Mounjaro works partly by slowing gastric emptying — the rate at which your stomach passes food into the small intestine. This is a well-recognised effect of GLP-1 receptor agonists, and tirzepatide, as a dual GIP and GLP-1 receptor agonist, shares this characteristic. When food sits in the stomach for longer than usual, fermentation by gut bacteria can produce sulphur-containing gases. Those gases, when released as burps, often carry a distinctive egg-like or unpleasant smell.

When are smelly burps most likely?

Many people notice them most strongly in the 24 to 72 hours following an injection, which aligns with when tirzepatide is most active in slowing digestion. They are also commonly reported after eating foods naturally high in sulphur — such as eggs, onions, garlic, broccoli, and cabbage. Reducing these foods temporarily can help some people, though individual responses vary considerably.

Is it the same as regular burping on Mounjaro?

Not always — general burping on Mounjaro is common and often odourless, caused simply by swallowing air or increased gas production. Smelly burps specifically tend to point to that slower gastric emptying effect. You can read more about the broader pattern of smelly burps on Mounjaro and how they differ across the titration stages, or explore sulphur burps on Mounjaro in more detail. Both experiences fall under the wider category of gastrointestinal side effects covered in the full Mounjaro side effects guide.

It is worth noting that smelly burps are unpleasant but generally considered a low-severity side effect. That said, if they are accompanied by severe or persistent nausea, vomiting, upper abdominal pain radiating to the back, or any symptom that feels unusual or worrying, contact your healthcare professional promptly — these could signal something that needs clinical attention.

One of the most useful things you can do with a recurring side effect like smelly burps is keep a consistent record — when they happen, how strong they are, and what you ate or drank beforehand. Patterns that feel vague day-to-day become much clearer when they are logged over several weeks.

GLP Trackr's side-effect tracker lets you log symptoms like burping and digestive discomfort after each dose, so you can see at a glance whether the timing lines up with your injections, a particular food, or a recent dose change. That kind of record is genuinely useful to bring to your next prescriber appointment — rather than trying to recall how things felt three weeks ago, you have an accurate, timestamped picture.

The app's food logging feature — including an AI photo scan that works even when appetite is low — also makes it straightforward to spot whether sulphur-heavy foods are clustering around your worst days. Connecting those dots is exactly what a tracking journal is designed for.

GLP Trackr is a companion app, not a medical service. It helps you observe and record your experience so you can have better conversations with your prescriber — it is not a substitute for their advice. If smelly burps are severe, persistent, or accompanied by other symptoms, always follow the guidance of your prescriber or doctor rather than self-managing.

Give your tracking a proper foundation — download GLP Trackr on the App Store or Google Play and explore it free for 7 days.