Do GLP-1 drugs need to be stopped before upper endoscopy?

If you take a GLP-1 drug such as semaglutide or tirzepatide and you are scheduled for an upper endoscopy, the short answer is: do not make a last-minute change on your own. A new randomized trial adds evidence that continuing these medicines can leave more stomach contents in place before the procedure, which may matter for sedation planning.

But the study did not show a higher rate of aspiration-related events, and the best plan can still depend on the procedure, your symptoms, and your overall risk. That is why instructions from a GI team or anesthesia team may differ from one patient to another.

What the new trial looked at

The OCULUS trial, published in JAMA Internal Medicine and indexed in PubMed, randomized 60 adults in the United States who were already taking GLP-1 or GLP-1/GIP medicines and were scheduled for elective upper endoscopy. One group held one dose before the procedure; the other group continued the medicine as usual.

The researchers measured clinically significant residual gastric volume, meaning stomach contents that could interfere with the exam, change anesthesia planning, or lead the care team to stop the procedure. In plain language, the study asked whether there was still a meaningful amount of food or liquid in the stomach at the time of the procedure.

What the study found

The main result was straightforward: clinically significant residual gastric volume was more common when the drug was continued than when one dose was held. The trial’s published key points report rates of 25.0% versus 3.1%.

That matters because upper endoscopy often uses sedation or monitored anesthesia care. If the stomach is not as empty as expected, the care team may need to adjust the procedure or anesthesia plan to lower the chance of regurgitation or aspiration.

Why this does not automatically mean harm happened

A higher rate of stomach contents does not automatically mean a patient will aspirate or have a complication. In this trial, there was no accompanying rise in aspiration-related adverse events.

That distinction matters. Studies can show a biologic or procedural risk marker without showing that patients were actually harmed at a higher rate. For readers, the practical takeaway is that the medicine may affect what the team sees and how they prepare, but the study does not prove that everyone who continues the drug will have a bad outcome.

How this fits with changing guidance

This study lands in the middle of a fast-changing guidance landscape. In 2023, the American Society of Anesthesiologists suggested holding GLP-1 medicines before elective procedures, including a one-week hold for weekly dosing. By late 2024, a multi-society update said most patients could continue GLP-1 drugs before elective surgery, with extra precautions for people at higher risk of delayed stomach emptying.

That shift reflects the balance clinicians are trying to strike: avoiding unnecessary medication holds while still reducing anesthesia and sedation risk in people more likely to have delayed gastric emptying.

Why advice can differ from person to person

Not every patient on a GLP-1 drug has the same risk. The care team may take into account:

whether the procedure is an upper endoscopy or something else
the type of sedation or anesthesia planned
current stomach or digestive symptoms such as nausea, vomiting, bloating, or early fullness
the specific GLP-1 medicine and dose
other conditions that slow stomach emptying
how long the person has been on the drug and whether the dose is being increased

The American Society of Anesthesiologists has said people at higher risk may need a liquid-only diet before the procedure, an adjusted anesthesia plan, or point-of-care ultrasound in some settings. That is one reason blanket advice often falls short.

Questions patients can ask before the procedure

If you are scheduled for endoscopy and take a GLP-1 medicine, it may help to ask your GI team or anesthesia team:

Should I continue my medicine or hold a dose before this procedure?
Does the plan change if I have nausea, reflux, bloating, or vomiting?
Does this apply differently for an upper endoscopy than for another test?
Should I follow a liquid-only diet before the procedure?
What should I do if I recently changed my dose?

If you are having severe vomiting, severe abdominal pain, trouble keeping down fluids, or symptoms that make you worried about dehydration or aspiration risk, contact your care team promptly. If symptoms are severe or you cannot safely wait, seek urgent care.

The bottom line

The newest randomized evidence supports what many clinicians have suspected: continuing GLP-1 drugs before upper endoscopy can leave more stomach contents behind. But it also shows that this does not automatically translate into harm, and it does not replace individualized instructions from your own care team.

For now, the safest message is simple: do not change a GLP-1 medicine on your own before an endoscopy. Ask the clinicians who know your procedure and your health history how they want you to prepare.

Sources

Editorial note: Weence articles are researched from cited public-health, medical, regulatory, journal, and reputable news sources and may be drafted with AI assistance. They are checked for source support, clarity, and safety guardrails before publication.

This article is for general informational purposes only and is not medical advice. Research findings can be early or incomplete, and health guidance can change. Always talk with a qualified healthcare professional about personal symptoms, diagnosis, medications, vaccines, screenings, or treatment decisions. If you think you may have a medical emergency, call emergency services right away.