They arrive with no warning, taste of rotten eggs, and are impossible to do discreetly. Here's what's actually going on, and what tends to help, including how this connects to GLP-1 medicines and your digestion more broadly.
The rotten-egg smell of sulphur burps can come from hydrogen sulphide gas produced when gut bacteria break down sulphur rich food. Diet, digestion speed, gut microbes and some gastrointestinal conditions can all potentially contribute.
What a sulphur burp actually is
The smell is often hydrogen sulphide, the same gas that gives rotten eggs and drains their particular character. 
Your gut bacteria produce it when they break down foods containing sulphur, which is completely normal and happens every day. What isn't typical is when enough of it builds up high enough in your digestive tract to come back up as a burp rather than leaving the usual way.
A few things commonly contribute: sulphur rich food in the system (eggs, red meat, garlic, onions, broccoli, cauliflower, cabbage, dairy, beer and wine, and some protein powders), how quickly digestion is moving, the balance of your gut bacteria, and in some cases an underlying gastrointestinal cause. It's rarely just about the egg on its own, diet and digestion tend to interact, similar to the broader causes of poor gut health.
What can slow digestion down or contribute
| Possible factor | What to notice |
|---|---|
| A big, rich, late meal | A commonly reported trigger for many people |
| GLP-1 medicines | Often reported in the days after a dose increase, alongside Mounjaro diarrhoea |
| Slow stomach emptying (gastroparesis) | Comes with early fullness, nausea, feeling stuffed after small meals |
| An infection (giardia) or H. pylori | Giardia is specifically linked to egg-smelling burps by NHS guidance; H. pylori is more associated with indigestion and stomach pain generally |
The infection route has the strongest medical backing here. NHS guidance specifically lists egg-smelling burps among the symptoms of giardiasis, an infection picked up from contaminated water, including abroad and occasionally from swimming, alongside diarrhoea and bloating, a pattern worth comparing against loose stool every morning and what causes urgent bowel movements. It doesn't clear on its own and needs treating, so persistent symptoms are a GP conversation rather than a wait and see. H. pylori, a stomach bacterium, can cause indigestion and stomach pain and is worth ruling out too, though sulphur burps aren't considered one of its defining symptoms. Bacterial overgrowth in the small intestine is a possible consideration if sulphur burps, bloating and irregular stools appear together over weeks rather than days, worth raising with a GP rather than something to self-diagnose.
What tends to help
Nothing makes them vanish instantly, but the following is commonly reported to help, often within a day or so, though this varies by person and cause. In the moment: drink water, stay upright for two to three hours after eating, and take a short walk to help the stomach empty. Over the next few days: find your trigger before you cut everything (eggs and protein shakes come up most often), eat smaller meals more often, slow down while eating, ease off alcohol for a week, and look at your protein powder, since whey is a commonly reported culprit and switching type sometimes helps. Pharmacists can advise on over the counter options for trapped wind and indigestion. Building a gut health baseline makes it easier to spot when something's genuinely changed, and if you'd rather not have to remember exactly what you ate and when, a gut health tracker like Gutsi can log your daily pattern for you, in the same spirit as tracking gut health at home more generally.
When to get it checked
Speak to a GP, or call 111, if sulphur burps come with any of these:
- Diarrhoea lasting more than a few days, particularly after travel or swimming in fresh water
- Losing weight without trying
- Stomach pain that is severe, or that keeps coming back
- Vomiting that won't settle
- Blood in your stool, or stool that is black and tarry
- Difficulty swallowing
- Burps happening most days for more than two weeks
Occasional sulphur burps after a heavy meal are ordinary. A pattern that persists is information, and it's worth someone looking at.
Find your one or two trigger foods rather than cutting everything, stay upright after eating, and if sulphur burps come with ongoing diarrhoea or bloating, see a GP rather than waiting it out. Watching for wider signs your gut health may be off is worth doing alongside this.
This article is for general information and is not medical advice. If you are worried about a change in your digestion, speak to a GP or call 111.
Gutsi provides lifestyle and wellness insights only. It is not intended to diagnose, treat, cure or prevent any disease, and should not be used as a substitute for professional medical advice.
