Stopping GLP-1s Before Surgery or Endoscopy: What Anesthesia Guidance Says

The short answer

Under multisociety guidance published in October 2024, most patients can continue GLP-1 medications such as semaglutide and tirzepatide before elective surgery. Patients at highest risk of stomach-emptying problems may be asked to follow a liquid diet for 24 hours before the procedure, and elective procedures may be postponed for people in the dose-escalation phase or with active GI symptoms. The decision belongs to your procedure team, so do not stop or change your medication on your own; tell them what you take, as early as possible.

This guide summarizes what that guidance says and gives you a checklist for the conversation. It is not a substitute for your surgeon's or anesthesiologist's instructions, which can differ for good reasons.

Why anesthesia teams care about GLP-1s

GLP-1 receptor agonists slow how quickly the stomach empties. That is part of how they reduce appetite. During anesthesia or deep sedation, protective airway reflexes are reduced, and food or liquid still in the stomach can be regurgitated and inhaled (aspiration). Fasting rules before procedures exist to keep the stomach empty, and delayed emptying can undercut them.

For endoscopy, retained stomach contents can also make it harder for the physician to see. That is why both anesthesia and gastroenterology groups were involved in the guidance.

What the 2024 multisociety guidance says

On October 29, 2024, the American Society of Anesthesiologists announced guidance developed with the American Gastroenterological Association, the American Society for Metabolic and Bariatric Surgery, the International Society of Perioperative Care of Patients with Obesity, and the Society of American Gastrointestinal and Endoscopic Surgeons. The main points, as described in the ASA announcement:

• Most patients can continue. Patients should continue taking GLP-1s before elective surgery, and those at low risk for delayed stomach emptying can keep taking them.
• Liquid diet for the highest-risk patients. People at the highest risk of significant GI side effects should follow a liquid diet for 24 hours before the procedure.
• Dose escalation is a risk period. Patients early in treatment, when doses are increasing, are at higher risk. This phase typically lasts four to eight weeks, and elective surgery should be deferred until it has passed.
• Active GI symptoms mean wait. Patients with nausea, vomiting, abdominal pain, shortness of breath or constipation should wait until symptoms have resolved before elective surgery.
• Higher doses carry more risk of GI side effects, and those patients should follow the liquid diet.
• Other conditions matter. Conditions that slow stomach emptying on their own, such as Parkinson's disease, may change the plan.
• Bedside ultrasound is an option. The team can use point-of-care ultrasound right before the procedure to check stomach contents in the highest-risk patients.
• Stopping has risks too. Teams should weigh delayed emptying against the risks of stopping, such as blood sugar changes in people with diabetes. The guidance also says withholding GLP-1s only because a patient has obesity or overweight could constitute bias and should be avoided.

Earlier, in 2023, ASA consensus guidance had recommended holding GLP-1s before elective procedures. The 2024 guidance moved away from routine holds for most patients. If you were told to stop before a past procedure, that may be why advice now sounds different.

Checklist: what to tell your anesthesiologist

Tell your team at the pre-procedure visit or phone screen, not on the morning of surgery. Bring this list:

Then ask three questions: Should I keep taking it as usual? Do I need a liquid diet before the procedure, and for how long? Who do I call if I develop GI symptoms before the date?

Endoscopy and colonoscopy: what's different

Upper endoscopy and colonoscopy are usually done with sedation, so the same aspiration concern applies. Two extra issues come up:

• Visibility. Food still in the stomach can make an upper endoscopy incomplete. If the physician can't see well, the procedure may need to be repeated, which means another round of preparation and sedation.
• Bowel preparation. Colonoscopy prep already involves a clear-liquid diet the day before. GI symptoms such as nausea or constipation, which GLP-1s can cause, can make prep harder. Tell the GI office about your GLP-1 when you schedule, not just at check-in, so they can give you instructions that account for it.

The October 2024 guidance was developed with the American Gastroenterological Association and the Society of American Gastrointestinal and Endoscopic Surgeons, so it is meant to apply to endoscopic procedures as well as surgery. Individual GI practices may still have their own protocols. Follow the instructions from the practice doing your procedure.

Who to ask what

• Surgeon or GI physician: whether the procedure is elective and can be moved if you are in dose escalation or have symptoms.
• Anesthesia team: fasting, liquid diet, and whether they plan a stomach ultrasound.
• Prescriber: whether any change to your GLP-1 is needed, and how to restart afterward. If you have diabetes, ask how to manage blood sugar if you are told to hold the drug.

Compounded, microdosed and research products

The guidance is about the drug class, not the brand. A compounded semaglutide or tirzepatide works through the same receptor. People sometimes leave compounded or "microdosed" GLP-1s off their medication list because they think of them as wellness products; that is the wrong instinct before anesthesia. Our pieces on the GLP-1 microdosing trend and compounded semaglutide add-ins explain what may be in those products.

The same goes for research-labeled peptides. You may feel awkward disclosing a product sold "for research use only," but your anesthesia team's job is to keep you safe, not to judge you. Our guide to peptide and prescription drug interactions covers why a complete list matters, and how to talk to your doctor about peptides has scripts for the conversation.

Where each drug fits

For background on the two most common GLP-1s, see our semaglutide and tirzepatide profiles. Oral forms are taken differently from weekly injections, so mention the form as well as the drug.

Dosing and any change to your prescription are set by your prescriber in coordination with your procedure team. PeptideOnline does not publish dosing protocols. See our medical disclaimer.

After the procedure. Ask before you leave when to restart, if you were told to hold the drug, and what to do if nausea from anesthesia overlaps with GLP-1 side effects. If you have diabetes, ask how to monitor blood sugar during the transition.

When to call before your procedure: if you develop vomiting, significant nausea, abdominal pain or bloating in the days before surgery or endoscopy, call the procedure team. They may want to reschedule. On the day, tell the anesthesiologist again even if you already reported it.