If you take Ozempic and have surgery, an endoscopy or a procedure under sedation coming up, the drug matters to your anesthesia team.
The concern is food left in the stomach. Under anesthesia, stomach contents can reach the lungs. That is called pulmonary aspiration.
The label warning itself is listed briefly in semaglutide side effects. This page covers what the societies advise and what the studies measured.
What the label says
The Ozempic label states that the drug delays stomach emptying [1]. It reports rare postmarketing cases of aspiration in people on GLP-1 drugs having elective surgery or procedures under general anesthesia or deep sedation.
Those people had food left in the stomach “despite reported adherence to preoperative fasting recommendations.”
The next sentence sets the limit. Available data are insufficient to say whether changing fasting rules or pausing the drug “could reduce the incidence of retained gastric contents.”
The label’s instruction to patients is short. Tell your healthcare providers before any planned surgery or procedure that you take the drug.
The Zepbound label carries the same warning in the same words for tirzepatide [2]. So do the Wegovy and Mounjaro labels.
What the societies advise
In 2024, five groups issued joint guidance [3]. They were the American Gastroenterological Association, the American Society for Metabolic and Bariatric Surgery and the International Society of Perioperative Care of Patients with Obesity.
The Society of American Gastrointestinal and Endoscopic Surgeons joined them. The American Society of Anesthesiologists’ council affirmed the value of the document.
Its starting point is shared decision-making between you, your prescriber and the procedure and anesthesia teams. It lists five things that raise the risk of slow emptying and aspiration.
| Factor | What the guidance says |
|---|---|
| Dose-escalation phase | Higher risk of delayed emptying than the maintenance phase |
| Higher dose | The higher the dose, the more likely stomach side effects |
| Weekly dosing | Stomach side effects are more common than with daily drugs |
| Stomach symptoms | Nausea, vomiting, belly pain, indigestion and constipation |
| Other conditions | Such as gastroparesis, bowel dysmotility and Parkinson's disease |
Without those factors, it says the drug may be continued before surgery. Where they are present, it weighs a pause against the risk of high blood sugar, the cost of bridging therapy and low blood sugar.
It also warns that holding the drug only because someone has obesity, with none of the risk factors, “could constitute overweight and obesity bias.”
If a hold is chosen
The guidance is plain that the right length of a hold “is unknown” [3]. It suggests following the original 2023 advice of the American Society of Anesthesiologists.
That advice was to hold daily drugs on the day of surgery and weekly drugs a week before. Everyone should still be checked for symptoms on the day.
The guidance then lists ways to lower the risk. One is a liquid diet for at least 24 hours before, as used before colonoscopy and bariatric surgery.
Another is a point-of-care ultrasound of the stomach on the day. A third is a rapid-sequence intubation, a faster way of securing the airway, weighed against canceling the procedure.
What the studies measured in the stomach
Most studies measure retained stomach contents, not aspiration itself. Retained food is a major risk factor for aspiration, but it is not the same event.
| Study and population | GLP-1 users | Controls |
|---|---|---|
| Upper endoscopy, semaglutide within 30 days, n=404 (retrospective) | 24.2% | 5.1% |
| Gastric ultrasound, once-weekly GLP-1, n=124 (cross-sectional) | 56% | 19% |
| Gastric ultrasound, semaglutide, 44 matched pairs (prospective) | 49% | 18% |
In the endoscopy study, the mean pause before the procedure was about 10 days [5]. It did not differ between people with and without retained food: 10.5 and 10.2 days. One aspiration was reported, in the semaglutide group.
In the ultrasound study of once-weekly drugs, the adjusted prevalence ratio was 2.48 (95% CI 1.23 to 4.97) [6]. The length of the pause was not linked to retained contents.
The matched study controlled for age, BMI and diabetes [7]. Solid food was found in 42% of semaglutide users against 7% of controls.
Its authors read that as a persistently raised risk “even after withholding one administration of semaglutide.”
A 2024 meta-analysis reviewed 14 studies with 2,143 adults [8]. In the studies of 1,011 patients that measured it, GLP-1 use was tied to more retained stomach contents: odds ratio 6.08 (95% CI 2.86 to 12.94).
What the studies found about aspiration
Aspiration itself is rare, which makes it hard to study. The same meta-analysis set it as a primary outcome, but pooled no aspiration rate [8].
Its aspiration evidence was the single case from the endoscopy study, plus a set of case reports showing solid food in the stomach despite proper fasting.
One large records study points the other way. It matched 296,389 pairs of adults with type 2 diabetes having surgery in the U.S. from 2016 to 2024 [9].
Aspiration occurred in 0.01% of those prescribed a GLP-1 drug and 0.03% of those who were not (relative risk 0.31). Its authors note it is unknown whether steps were taken to reduce the risk.
So the evidence splits in two. Food left in the stomach is clearly more common. Whether that turns into more aspiration in practice has not been shown, and the labels say the data are insufficient.
What this means before a procedure
The one step every source agrees on is disclosure. Tell your surgeon, endoscopist and anesthesia team that you take a GLP-1 drug, and how long you have been on your dose.
Whether to pause is their call with you, not a rule to apply alone. Stopping has its own effects, covered in what happens when you stop taking semaglutide.
Mention stomach symptoms too, since the guidance lists them as a risk factor. That includes nausea and burping, covered in Ozempic nausea and sulfur burps on Ozempic.
If you are still raising your dose, say so. The guidance treats the escalation phase as higher risk, and the steps are in semaglutide dosage. The tirzepatide warnings are in tirzepatide side effects.