The Pre-Op Checklist: Exactly What to Tell Your Surgical Team

The American Society of Anesthesiologists (ASA) issued consensus-based guidance in 2023 (updated 2024) recommending that GLP-1 medications be held before elective procedures requiring sedation or general anesthesia. This guidance applies to all GLP-1 receptor agonists — semaglutide, tirzepatide, liraglutide, and dulaglutide — and to all formulations, including compounded versions.

This guide covers what to tell your surgical team, when to stop your medication, and what to do about resuming treatment after the procedure.

What to Disclose — The Non-Negotiables

At minimum, inform every member of your surgical team — surgeon, anesthesiologist, and pre-op nursing — of the following:

That you are on a GLP-1 medication. State the specific medication name (semaglutide or tirzepatide), the dose, and when your last injection was. This information should appear on your medication list, but verbal confirmation prevents it from being overlooked during a chart review.

Whether it's compounded or brand-name. Compounded medications may not appear in standard drug interaction databases. If your GLP-1 is compounded, say so explicitly — some anesthesiologists are less familiar with compounded formulations and may not associate them with the same gastric emptying concerns.

Your last dose date. This is critical for the anesthesiologist's assessment of residual gastric contents. A GLP-1 injection 2 days before surgery poses different risk than one 7 days before.

Whether you've experienced GI symptoms. Active nausea, vomiting, or significant gastroparesis symptoms increase the concern for residual gastric contents. An asymptomatic patient who held the medication for the recommended period is lower risk than a symptomatic patient who injected 3 days ago.

When to Stop — The ASA Framework

The ASA's consensus guidance recommends holding GLP-1 medications before elective procedures as follows. These timelines are based on clinical judgment and the medications' pharmacokinetics, not randomized trial data — no such trials exist for this specific question.

Weekly injectable semaglutide or tirzepatide: Hold for at least 7 days before the procedure. Some anesthesiologists prefer 2–3 weeks, particularly at higher doses or if the patient has significant GI symptoms. Discuss the specific timeline with your anesthesiologist during the pre-op visit — not on the morning of surgery.

Daily injectable liraglutide: Hold for at least 1 day before the procedure. The shorter half-life (approximately 13 hours) means a shorter hold is sufficient.

Oral semaglutide (Rybelsus or compounded oral): Hold for at least 1 day before. Oral formulations have faster clearance than injectable depot formulations.

Emergency surgery: If surgery cannot be delayed (trauma, acute appendicitis, bowel obstruction), the anesthesiologist will treat the patient as a full-stomach case regardless of when the last dose was. This means rapid-sequence intubation and full aspiration precautions. You cannot control the timing of emergency surgery — just ensure GLP-1 therapy is documented on your emergency contact information and medical ID.

What Happens If You Don't Disclose

The risk is pulmonary aspiration. Here's the mechanism in plain terms.

GLP-1 receptor agonists slow the rate at which your stomach empties its contents into the small intestine. Under normal circumstances, the stomach empties within 4–6 hours after a meal. On a GLP-1, food and liquid can remain in the stomach significantly longer — sometimes 12–24 hours or more, depending on the dose and the individual patient.

Standard pre-operative fasting instructions (nothing to eat for 8 hours, nothing to drink for 2 hours) were designed for patients with normal gastric emptying. They may not be sufficient for GLP-1 patients, who can have substantial residual gastric contents even after 12+ hours of fasting.

During general anesthesia or deep sedation, the muscles that normally protect the airway from stomach contents relax. If there is food, liquid, or gastric acid in the stomach, it can travel up the esophagus and into the lungs. Pulmonary aspiration can cause chemical pneumonitis, aspiration pneumonia, acute respiratory distress syndrome (ARDS), and in severe cases, death.

This is rare even in GLP-1 patients, but it is preventable when the anesthesiologist knows about the medication and can adjust their approach accordingly — longer fasting times, point-of-care gastric ultrasound to assess stomach contents, rapid-sequence intubation if needed, or rescheduling the procedure after a longer medication hold.

Procedures That Require Disclosure

General anesthesia (any surgery): Always disclose. This includes elective procedures like joint replacements, hernia repairs, gallbladder removal (notably more common in GLP-1 patients), and cosmetic surgery.

Sedation for endoscopy or colonoscopy: Always disclose. Upper endoscopy (EGD) is particularly relevant because residual gastric contents can obscure the endoscopist's view and increase aspiration risk. Some GI practices now specifically ask about GLP-1 use during scheduling. If they don't ask, volunteer the information.

Dental procedures under IV sedation: Always disclose. This is the most commonly missed scenario — patients forget to mention GLP-1s to their dentist because they don't think of dental work as "surgery." Any procedure involving IV sedation carries aspiration risk. Routine dental cleanings or procedures under local anesthesia only do not require GLP-1 disclosure for aspiration purposes, though there are separate considerations for general medication disclosure.

Moderate sedation for imaging (MRI with sedation, certain biopsies): Disclose if sedation is planned.

Resuming After Surgery

Your prescriber's guidance takes priority, but the general approach is:

After outpatient/same-day procedures: Most patients can resume their GLP-1 on their next scheduled injection day, provided they're eating, drinking, and have no surgical complications that affect GI function. If the procedure involved the GI tract (endoscopy, gallbladder surgery, bariatric surgery), your surgeon should clear you before resuming.

After major surgery or hospital admission: Resume only after you're tolerating a regular diet and have discussed timing with both your surgeon and your GLP-1 prescriber. Post-surgical ileus (temporary intestinal shutdown) plus GLP-1-mediated gastric slowing can compound, so timing matters.

If you missed 2+ weeks: If the medication hold extends beyond 2 weeks, your prescriber may recommend restarting at a lower dose and re-titrating, particularly if you're on a higher maintenance dose. See our Missed Dose Decision Tree for detailed guidance.

A Note for Your Medical Records

If you're on a compounded GLP-1 from a telehealth platform, your hospital or surgical center's records may not include it. Telehealth prescriptions don't automatically sync to hospital systems. Add your GLP-1 to your medication list in your PCP's patient portal, carry a written medication list to every pre-op appointment, and state the medication verbally during the pre-op interview. Redundancy is protection.

If you wear a medical ID bracelet or use a medical ID app on your phone, add your GLP-1 to it. In an emergency where you cannot communicate, this information could prevent a dangerous interaction.