Retatrutide side effects: what sulphur burps actually tell you

What did @stanmilsom1 actually say?

Stan woke up with what he called "the eggy burps" after a weekend of eating rich, oily food while on retatrutide. He attributed the sulphur burps to the food rather than purely to the peptide, and said he cleared the symptoms by going for a long walk and sipping water steadily throughout the morning. He also skipped his usual oats, had a small amount of fibre, and took his electrolytes. His conclusion: "things like this happen to everyone" and it's about managing them quickly.

To his credit, he didn't claim retatrutide cured anything, didn't recommend a dose, and framed this as a personal experience rather than medical advice. That restraint matters, and it's rarer than it should be in this corner of TikTok.

Does the science back this up?

Partly, yes. Sulphur burps on GLP-1 receptor agonists and dual/triple agonists like retatrutide are a well-documented side effect tied to delayed gastric emptying, not some mysterious reaction. The mechanism is fairly straightforward, and his remedies have some physiological logic behind them.

Retatrutide acts on GIP, GLP-1, and glucagon receptors simultaneously. Delayed gastric emptying is one of its most consistent gastrointestinal effects, meaning food, including sulphur-containing proteins and fats, sits in the stomach longer and ferments. This produces hydrogen sulphide gas, which is exactly what causes that rotten-egg odour. The Phase 2 trial of retatrutide (Jastreboff et al., 2023, New England Journal of Medicine) reported nausea, vomiting, and GI-related adverse events in a substantial proportion of participants, particularly at higher doses. Walking does accelerate gastric motility. A review by Soffer et al. (1994, Digestive Diseases and Sciences) found that moderate physical activity speeds gastric emptying, which is a real mechanism for why Stan's walk may have helped. Staying hydrated without gulping large volumes is also sensible, since large water boluses can temporarily worsen bloating in people with slowed gastric emptying.

What did they get wrong (or right)?

Stan got more right than wrong here, but he undersells the peptide's role. Blaming the oils and restaurant food entirely isn't the full picture. Retatrutide's gastric slowing means almost any heavy meal carries more GI risk than it would off-drug. The food was a trigger, but the drug set the conditions.

His fix, walking and steady hydration, is genuinely reasonable and has mechanistic support. Skipping his usual oats temporarily was also sensible. High-fibre foods in the context of delayed gastric emptying can worsen bloating and gas production, so reducing fibre acutely during a GI flare is a reasonable short-term strategy, though this isn't a reason to avoid fibre long-term.

What he didn't address is when sulphur burps should prompt more concern. Persistent, severe GI symptoms on any GLP-1-based compound can occasionally signal more serious issues, including gastroparesis rather than simple delayed emptying. If symptoms last more than a day or two, that warrants a clinical conversation, not just a longer walk.

What should you actually know?

Retatrutide is still in clinical trials. It is not approved by the FDA or any major regulatory body as of mid-2025. Anyone using it outside a supervised clinical study is using an investigational compound with an incomplete long-term safety profile. That doesn't mean the side effect management tips here are wrong, but the context matters enormously.

Sulphur burps on triple agonists like retatrutide are common enough that users should plan for them, particularly around meals high in fat, sulphur-rich proteins (eggs, meat, certain vegetables), or alcohol. General strategies that have support in the GI literature include:

• Eating smaller, lower-fat meals, especially in the first weeks of use or after a dose increase.
• Avoiding carbonated drinks, which add gas volume to an already-slowed system.
• Moderate post-meal walking, which has genuine evidence for improving gastric motility.
• Staying hydrated consistently rather than in large amounts at once.

If you are using any investigational peptide or compounded GLP-1-adjacent compound, these GI effects are not just inconvenient. They are signals from your gut that the drug is working as intended, and that your diet needs to adapt around it, not the other way around.