GLP-1 Medications and Surgery: Why the Stomach Matters

If you take a GLP-1 medication and a procedure is on the calendar, you may have heard that the two need some planning. The reason has to do with how these medications affect the stomach. This is general education, not medical advice, and it is not a substitute for instructions from your own care team.

Why the stomach matters

GLP-1 medications slow how quickly food leaves the stomach. That is part of why people feel full for longer, a theme we touch on in our guides to the hormones behind hunger and food noise. It also raises a question for anesthesia. Procedures that use sedation or general anesthesia usually require an empty stomach, because stomach contents that travel into the airway can cause serious problems. If the stomach empties slowly, some food may remain even after the usual fasting window.

How the advice has changed

Early advice from anesthesiology groups was cautious, and it often suggested pausing these medications before a procedure. More recently, five medical societies published joint multisociety guidance. It was authored by Kindel and colleagues and published in October 2024 in Surgery for Obesity and Related Diseases and other society journals. The societies were the American Gastroenterological Association, the American Society for Metabolic and Bariatric Surgery, the American Society of Anesthesiologists, the International Society of Perioperative Care of Patients with Obesity and the Society of American Gastrointestinal and Endoscopic Surgeons.

• Many people may continue. Coverage of the guidance describes continuing the medication before elective surgery or endoscopy as reasonable for patients who do not have a higher risk of delayed stomach emptying.
• Risk is weighed, not assumed. For people who do have a higher risk, clinicians balance the chance of stomach contents in the airway against the risks of stopping, such as blood sugar rising in people who take these medications for diabetes.
• A liquid diet for a day may be used. For people considered at higher risk, summaries mention a 24-hour clear liquid diet before the procedure, similar to the preparation used for a colonoscopy.
• Extra checks are possible. A quick ultrasound of the stomach can show whether food remains, and anesthesiologists have techniques to protect the airway when there is concern.

What the guidance is, and is not

The authors describe this as guidance, not a formal evidence-based guideline, because high-quality trials are limited. Several authors also reported ties to industry. It is meant to support individual decisions, and the best plan can depend on the type of medication, how long you have taken it, your symptoms and the procedure.

Practical points for patients

• Tell everyone involved. Mention your GLP-1 medication to the surgeon, the anesthesia team and the endoscopy team, along with every other medication and supplement you take.
• Ask for written instructions. Ask whether to continue or hold the medication, and what to eat and drink beforehand. Plans differ, so follow the one you are given.
• Do not change your medication on your own. Stopping can bring back appetite and, for some people, affect blood sugar, so it is a decision for you and your care team.
• Mention symptoms. Ongoing nausea, vomiting or a feeling of fullness on the day of a procedure is worth telling the team about.

Where this fits in the bigger picture

Planning around a procedure is one piece of using these medications thoughtfully. Our other guides cover who qualifies, eating well while taking one and the newer oral options.

Sources

• Kindel TL, et al. Multisociety clinical practice guidance for the safe use of glucagon-like peptide-1 receptor agonists in the perioperative period. Surgery for Obesity and Related Diseases, 2024 (DOI 10.1016/j.soard.2024.08.033; details from society and news summaries, check the paper for exact wording).
• American Society of Anesthesiologists and partner societies, public statements on GLP-1 receptor agonists before procedures.