Sulfur Burps on Ozempic (semaglutide 0.5-2 mg): Week-by-Week Timeline of What to Expect

What the Ozempic label reports about burping

The label's word for belching is eructation, listed among gastrointestinal reactions reported in fewer than 5% of patients in the pooled placebo-controlled trials: 262 patients on placebo, 260 on 0.5 mg and 261 on 1 mg, mean exposure 32.9 weeks [1]. Eructation was reported by 0% of the placebo group, 2.7% of the 0.5 mg group and 1.1% of the 1 mg group [1]. The label records the event without saying why some burps smell of sulfur [1].

Is there a week-by-week timeline?

The label's nearest timing information concerns other gut symptoms: most reports of nausea, vomiting and/or diarrhea occurred during dose escalation rather than at a stable dose [1]. That finding is about those three symptoms, not burping, and the label gives no duration or onset for belching.

Where the dose steps fit

Ozempic starts at 0.25 mg once weekly for 4 weeks, a dose the label says is not for maintenance, then 0.5 mg. The dose can rise to 1 mg after at least 4 weeks on 0.5 mg, and to 2 mg after at least 4 weeks on 1 mg; 2 mg is the maximum weekly dose [1].

Higher doses have been compared. In a 40-week trial of 959 patients on Ozempic 1 mg or 2 mg with metformin, with or without a sulfonylurea, gastrointestinal reactions were reported in 30.8% on 1 mg and 34% on 2 mg, with no new safety signals [1]. That compares gastrointestinal reactions as a group, not belching.

What the label warns about

Belching is not among the label's serious adverse reactions. The label warns about other gut events [1]:

• Severe gastrointestinal adverse reactions in 0.4% of patients on 0.5 mg and 0.8% on 1 mg, versus 0% on placebo [1].
• Ozempic is not recommended in people with severe gastroparesis [1].
• Acute pancreatitis has been observed with GLP-1 receptor agonists including Ozempic; the label describes its signs as persistent or severe abdominal pain, sometimes radiating to the back, with or without nausea or vomiting [1].
• Acute kidney injury from volume depletion, mostly after gastrointestinal reactions such as nausea, vomiting or diarrhea led to dehydration; the label says to monitor renal function in patients reporting such reactions, especially during initiation and dose escalation [1].

The label also lists postmarketing reports of ileus, intestinal obstruction and severe constipation with fecal impaction, without an estimated frequency because frequency cannot be calculated from voluntary reports [1].

Do the tablets cause burping too?

Burping appeared in the Rybelsus tablet trials: 0.6% at 7 mg and 2% at 14 mg, versus 0% on placebo [2]. Rybelsus and Ozempic tablets are not substitutable mg for mg, and those figures do not establish a rate for Ozempic tablets [2].