"Sulfur burps": real, and unstudied

Why this page exists: this question comes up often in GLP-1 patient forums but rarely in search results. We sampled forum threads by title; we did not quote or identify any user.

What the labels report

Eructation, the medical term for burping, was reported by 7% on Wegovy 2.4 mg against under 1% on placebo.^[1] On Zepbound it was 4%, 5% and 5% at 5, 10 and 15 mg, against 1%.^[2] So burping is clearly a drug effect. Abdominal bloating (distension) was 7% versus 5% on Wegovy, and flatulence 6% versus 4%.^[1]

Share reporting eructation (burping), drug vs placebo.^[1][2]

Why the smell, honestly

No trial recorded what burps smelled like. The common explanation is that food sits longer in a slowed stomach and gut, and gut bacteria break down sulfur-containing foods into hydrogen sulfide, the rotten-egg gas. That fits with how these drugs slow stomach emptying, but it has not been tested in GLP-1 users, so treat it as a plausible idea rather than a finding.^[3]

When it is not just burping

• Burping with vomiting, especially of food eaten many hours earlier
• Burping with severe or persistent belly pain or a swollen belly
• Burping with diarrhea you cannot keep up with

The labels warn about severe gut reactions and, in reports after marketing, bowel obstruction; these combinations are reasons to call.^[1][2]

The short version

Questions to bring to your prescriber

Print these or screenshot them. They are conversation starters, not a checklist of things to do.

• Is my burping a sign that my stomach is emptying very slowly, and should we look into it?
• Are any over-the-counter remedies for gas safe with my other medicines?

Sources

Every number on this page traces to one of these. "Primary read" means the full paper or label was read; "abstract only" means only the abstract was available; "secondary" means the figure was taken from a named review.

1. Novo Nordisk / FDA. Wegovy (semaglutide) injection and tablets, prescribing information, revised 06/2026. label
2. Eli Lilly / FDA. Zepbound (tirzepatide) prescribing information, revised 08/2026. label
3. Hiramoto B et al. Quantified metrics of gastric emptying delay by GLP-1 receptor agonists: systematic review and meta-analysis. Am J Gastroenterol 2024;119:1126–40. primary read · meta-analysis

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