What Causes Sulfur Burps on a GLP-1?
Nobody knows for sure. GLP-1 drugs like Zepbound and Ozempic list burping as a side effect, and they slow how fast the stomach empties. The rotten-egg smell comes from hydrogen sulfide, a gas that gut microbes make when they break down sulfur-containing compounds, like the ones in protein. A reasonable explanation is that food sitting in the stomach longer gives more time for that gas to form. But no study has tested that directly.
Here's how often burping itself shows up on the four labels:
The labels call it "eructation," the medical word for burping.
What Are Sulfur Burps?
A sulfur burp is a burp that smells or tastes like rotten eggs. That smell comes from hydrogen sulfide, which the CDC describes as a colorless gas that smells like rotten eggs.
Burping itself is normal. NIDDK says people typically belch up to 30 times a day, and that some people belch a lot because they swallow too much air. It's the sulfur that makes some burps stand out.
Where Does the Sulfur Come From?
Mostly from your gut microbes. The CDC notes that bacteria in the digestive tract produce hydrogen sulfide as they digest protein-containing food. A research review explains that sulfur compounds in the colon come from inorganic sources, like sulfates and sulfites, and organic ones, like dietary amino acids. A group called sulfate-reducing bacteria are among the best studied, and they're common residents of the colon.
Protein matters here. In a small study of 5 men, eating more meat raised the amount of sulfide in their stool roughly fifteenfold, from a meat-free diet to 600 grams a day. The authors concluded that dietary protein from meat is an important fuel for sulfide production in the large intestine.
One important limit: nearly all of this research measured gas in the colon and stool, not in burps. A classic 1998 study found hydrogen sulfide was the main sulfur gas in flatus, and odor was significantly linked to its concentration. Whether the same thing happens in the stomach to produce a sulfur burp is much less studied.
So Why Might a GLP-1 Cause Them?
Here's the part we want to be careful with, because it gets overstated a lot.
What we know: every GLP-1 label says the drug delays gastric emptying, and burping is a listed side effect. Many people on these drugs are also advised to prioritize protein. And the Wegovy label says GI reactions, including burping, were most frequently reported during dosage escalation.
What's a reasonable guess: food, especially protein, sits in a slower stomach longer, which could give more time for sulfur gases to form before they come back up. Think of the stomach as the first stop on a conveyor belt. When that stop slows down, what's sitting there has more time to change.
What we couldn't find: any .gov or .edu source or published study that directly links GLP-1 drugs, or slow stomach emptying, to sulfur burps. So treat the explanation above as a plausible idea, not an established fact. We covered slow stomach emptying in more depth in GLP-1 and Gastroparesis.
How to Get Rid of Sulfur Burps
No remedy has been tested for GLP-1 sulfur burps specifically. These are the most sensible places to start, based on general NIDDK gas guidance and what's known about how the gas forms.
Eat Smaller Meals
NIDDK says your doctor may recommend eating smaller, more frequent meals to ease gas symptoms. On a GLP-1, a smaller meal also means less food sitting in a stomach that's emptying slowly.
Spread Your Protein Out
You don't need to cut protein, which matters for keeping muscle while you lose weight. But if sulfur burps follow a big protein-heavy meal or a large shake, try spreading the same amount across more, smaller servings. This is a practical experiment, not something that's been tested for sulfur burps.
Swallow Less Air
NIDDK says swallowing less air may help ease gas symptoms, especially if you belch a lot. That means avoiding gum, hard candy, and fizzy drinks, eating and drinking more slowly, and not smoking. Swallowed air doesn't cause the sulfur smell, but it can mean more burps overall.
What Drink Gets Rid of Sulfur Burps?
We couldn't find evidence that any particular drink stops them. Plain water is a sensible choice, because staying hydrated matters on a GLP-1, especially if diarrhea is part of the picture. Skip carbonated drinks, which NIDDK lists among the common causes of swallowed air.
Can Pooping Relieve Sulfur Burps?
Not directly. Burps come from the stomach, and bowel movements empty the colon, so one doesn't clear the other. That said, if you're constipated, getting things moving may help you feel less full and gassy overall. We covered that in GLP-1 Constipation.
Does Pepto-Bismol Help Sulfur Burps?
It might, and there's a chemical reason why. Its label lists belching from overindulgence among its uses, but no study has tested it on sulfur burps specifically, and it's not right for everyone.
Pepto-Bismol's active ingredient is bismuth subsalicylate. Bismuth binds to hydrogen sulfide. In a 1998 study, 10 healthy people took bismuth subsalicylate four times a day for 3 to 7 days, and it produced a greater than 95 percent reduction in fecal hydrogen sulfide release. That's a small, uncontrolled study, and it measured gas from stool, not burps. Still, it's the best direct evidence that bismuth can capture the rotten-egg gas.
Before you reach for it, know the cautions. MedlinePlus says to talk to your doctor before taking bismuth subsalicylate if you take blood thinners such as warfarin, a daily aspirin, or medication for diabetes, arthritis, or gout. That caution is worth taking seriously on any GLP-1, since these drugs affect blood sugar even when they're prescribed for weight, and especially if you also take insulin or another diabetes medicine. MedlinePlus also says to ask your doctor first if you've ever had an ulcer, a bleeding problem, bloody or black stools, or kidney disease. It's a salicylate, related to aspirin, so skip it if you're allergic to aspirin. The product's own label says to stop use and ask a doctor if symptoms get worse or last more than 2 days, or if you notice ringing in your ears. It also says children and teenagers who have or are recovering from chickenpox or flu-like symptoms should not use it, so check with a doctor before giving it to anyone under 18.
One more thing that surprises people: it can darken your tongue and stool. MedlinePlus says that's harmless and usually goes away a few days after you stop. But black stool can also be a sign of bleeding, so if you're not sure which it is, ask. We looked at Pepto-Bismol's role in the upper gut in Does Pepto-Bismol Help Acid Reflux?
Do Probiotics Help Sulfur Burps?
"Probiotics for sulfur burps" is a popular search, but we couldn't find any evidence that they help. NCCIH, part of the NIH, notes that much remains to be learned about whether probiotics are helpful and safe for various health conditions, and that some products have been found to contain microorganisms other than those on the label. NIDDK recommends that you talk with your doctor before using supplements, probiotics, or any complementary or alternative medicines.
How Long Do Sulfur Burps Last?
We couldn't find any study that measured it, on a GLP-1 or otherwise. The closest clue is the Wegovy label's note that GI reactions like burping were most frequently reported during dosage escalation. The Zepbound label also says tirzepatide's effect on stomach emptying is largest after the first dose and diminishes over time. That suggests burping may be more likely around dose increases, though no study has tracked how long sulfur burps last. If they don't ease, tell your prescriber.
Sulfur Burps With Diarrhea or Vomiting
This combination is one of the most searched versions of the question, and it's where you want to pay closer attention.
On a GLP-1, diarrhea and vomiting are common side effects on their own, especially after a dose increase. We covered diarrhea in GLP-1 and Diarrhea and vomiting in our guide to GLP-1 nausea.
But not everything is the medication. Stomach infections can cause gas, cramps, and diarrhea too. For example, the CDC lists diarrhea, gas, smelly greasy poop that can float, stomach cramps, and upset stomach or nausea as common symptoms of Giardia, a parasite that spreads through contaminated water, food, surfaces, or person to person. You'll see Giardia linked to sulfur burps online, but the CDC's symptom page doesn't mention burps, so we can't confirm that link. The point is simply this: if these symptoms start suddenly, especially after travel, camping, or a new water source, don't assume it's your GLP-1.
When to See a Doctor
NIDDK says adults should see a doctor right away for:
- Diarrhea lasting more than 2 days
- A high fever
- Six or more loose stools a day
- Frequent vomiting
- Severe pain in the abdomen or rectum
- Stools that are black and tarry, or contain red blood or pus
- Signs of dehydration
- A change in mental state, such as irritability or lack of energy
NIDDK's signs of dehydration include extreme thirst or dry mouth, urinating less than usual, feeling tired, dizzy, or lightheaded, and dark-colored urine. Dehydration deserves extra care on a GLP-1, because the labels warn about acute kidney injury from fluid loss, including from vomiting and diarrhea.
Do Sulfur Burps Mean You're Losing Weight?
No. We couldn't find any evidence that sulfur burps are a sign the drug is "working" or that you're losing more weight. They're a side effect, not a progress marker. Weight loss on these drugs happens whether or not you ever have one.
Do Sulfur Burps Mean I'm Sick?
Often not, especially if they started with your GLP-1 or a dose increase and you feel otherwise well. But get medical care promptly if burps come with severe or persistent stomach pain (especially pain that spreads to your back), vomiting you can't stop, fever, yellowing of the skin or eyes, or diarrhea lasting more than 2 days. The GLP-1 labels warn about pancreatitis and gallbladder problems. And don't stop your GLP-1 on your own because of burps. Talk to your prescriber, who can weigh a slower dose schedule.
The Better Question
Let's step back.
Most of what you'll read about sulfur burps focuses on the medication. We've covered that above, and your prescriber is the right person for that part.
But there's a broader question worth asking about digestion in general: "what am I eating, and how does my gut handle it?" Everyone's gut microbes ferment food and make gas as part of normal digestion, and differences in those microbes may be one reason some people's gas is more noticeable than others'. That's a question about your plate and your gut, and it's one you can learn a lot about. We dug into the everyday side of it in Gas and Bloating: The Symptom Everyone Accepts But Shouldn't.
Everyday digestive comfort is what Atrantil was designed around. It's a polyphenol formula designed to support digestive comfort and help with occasional bloating and gas. Its published data is early: a small 2016 retrospective case series led by the formula's developer, with no control group. It hasn't been studied for sulfur burps or in people taking GLP-1 drugs, and it isn't a treatment for any medication side effect. If occasional gas and bloating are part of your picture, it's worth asking your prescriber about.
Understanding how your own digestion works helps you ask better questions and have better conversations with your healthcare provider. If you want a starting point, take the quiz. For the full picture of GLP-1 digestive effects, see our complete guide.
About Re:garding Your Gut
Re:garding Your Gut is a polyphenol-powered gut health brand founded by Kenneth Brown, MD, a board-certified gastroenterologist with more than 20 years in practice. The product family includes Atrantil for bloating and gas, Re:flux for acid reflux, and Re:balance for microbiome support.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is educational and is not medical advice, and it is not a substitute for your medication's prescribing information or your prescriber's advice. Do not start, stop, or change the dose of a prescription medication based on this article. Talk to your healthcare provider before adding any supplement while taking a GLP-1 medication.
