By Christopher Delp, MD, Medical Director, Duluth Med Spa. In practice since 1992.
Last reviewed: July 2026
If you take semaglutide, tirzepatide, or any GLP-1 medication and you have a procedure scheduled, tell your surgeon and your anesthesia team. Give them the drug name, the dose, and the date of your last injection. This is one of the most important and least discussed parts of GLP-1 care, and most patients have never been told.
Here is what is actually going on, what the current guidance says, and what you should do.
Why does a weight loss medication matter to an anesthesiologist?
GLP-1 medications slow gastric emptying. That is part of how they work. Food stays in your stomach longer, you feel full sooner, and you eat less.
That same effect creates a problem under sedation. Anesthesia relaxes the reflexes that normally keep stomach contents out of your airway. If your stomach still has food or fluid in it when those reflexes are suppressed, there is a risk of aspiration, meaning stomach contents entering the lungs. Aspiration is uncommon, but it is serious when it happens.
The FDA took this seriously enough that in late 2024 it added an aspiration warning to the labeling of all GLP-1 medications.
The concern is not that GLP-1 medications are dangerous. The concern is that a standard overnight fast may not empty your stomach the way your care team assumes it will.
How real is this risk?
The evidence shows a clear signal on one measure and a less clear signal on another, and you deserve the honest version of both.
Patients on GLP-1 medications are substantially more likely to have food still in the stomach at the time of a procedure. A study published in JAMA Surgery found residual stomach contents in 56 percent of GLP-1 users compared with 19 percent of non-users, even after appropriate fasting.
Whether that translates into more actual aspiration events is less clear. Aspiration remains rare overall, in the range of 0.02 to 0.07 percent of surgical patients, and the data on whether GLP-1 use meaningfully increases that number is mixed.
So: more food left in the stomach, clearly yes. More aspiration events, not cleanly demonstrated. That combination is why the guidance has moved toward assessing each patient on the day of the procedure rather than applying one blanket rule to everyone.
Do I have to stop my GLP-1 before surgery?
Probably, but the timing is not as simple as it once looked, and the guidance has genuinely changed.
What the original guidance said
In June 2023, the American Society of Anesthesiologists recommended holding weekly GLP-1 medications for one week before an elective procedure, and daily formulations on the day of the procedure.
Why one week may not be enough
Semaglutide has a half-life of roughly one week. According to its FDA labeling, the drug is still present in your circulation for about five weeks after your last dose. That means a seven-day hold clears only about half of it.
The research bears this out. In the JAMA Surgery study mentioned above, holding the medication for up to seven days did not reliably reduce the amount of food left in patients’ stomachs. A one-week hold, on its own, did not solve the problem.
What many teams do now
Because of this, a lot of surgeons and anesthesia groups now ask patients to hold weekly GLP-1 medications for one to two weeks before a procedure, with the longer end preferred for major surgery. Research presented to the American Academy of Orthopaedic Surgeons in 2025 found that patients undergoing hip and knee replacement had lower complication rates when the medication was stopped at least 14 days beforehand.
What the societies currently recommend
In October 2024, a joint statement from the American Society of Anesthesiologists, the American Gastroenterological Association, the American Society for Metabolic and Bariatric Surgery, and other groups moved away from a fixed hold entirely. Their position is that most patients can continue their GLP-1, and that higher-risk patients, including those still increasing their dose and those with nausea, vomiting, or bloating, should follow a liquid-only diet for at least 24 hours beforehand. The anesthesia team may also use bedside ultrasound to check whether the stomach is empty, or adjust their airway technique.
Where that leaves you
There is no single universal rule right now, and any source that gives you one is oversimplifying. In our practice, we generally advise planning for a one to two week hold for weekly GLP-1 medications, with the longer end for major surgery, and we always defer to the surgical and anesthesia team’s specific instructions.
Do not stop your medication on your own. Ask your prescriber and your proceduralist to make that decision together. And if you have diabetes, never stop a GLP-1 without a plan to manage your blood sugar in the meantime.
To be clear, this applies to procedures involving anesthesia or sedation. It does not apply to in-office aesthetic treatments where you are awake.
What should I actually say?
Tell every surgeon, anesthesiologist, proceduralist, and pre-op nurse the following, without waiting to be asked:
– The name of your medication (semaglutide, tirzepatide, or another GLP-1)
– Your current dose
– The date of your last dose
– Whether you are still increasing your dose or are on a stable dose
– Whether you have had nausea, vomiting, bloating, or a sensation that food is sitting in your stomach
Then ask three questions:
– How far in advance do you want me to hold my medication?
– Should I follow a clear liquid diet for 24 hours before the procedure?
– Will you coordinate the timing with my prescriber?
Follow every fasting instruction exactly. And if you feel nauseated, bloated, or full on the morning of your procedure, say so before you go back. That single sentence can change how your team manages your airway.
What if my surgeon does not ask about it?
Tell them anyway. This guidance is recent, it has already changed once, and not every clinician has caught up. You are not being difficult by volunteering it. You are giving your team information they need.
The bottom line
GLP-1 medications are safe and effective, and this is a manageable issue, not a reason to avoid treatment. But it is your responsibility, and ours, to make sure the people sedating you know what you are taking.
If you are a patient of ours and you have a procedure coming up, call us. We will talk through the timing with you and coordinate with your surgical team.
References
American Society of Anesthesiologists, Consensus-Based Guidance on Preoperative Management of Patients on GLP-1 Receptor Agonists (June 2023)
American Society of Anesthesiologists and multisociety partners, updated GLP-1 perioperative guidance (October 2024)
https://www.asahq.org/about-asa/newsroom/news-releases/2024/10/new-multi-society-glp-1-guidance
Sen S, et al. GLP-1 Receptor Agonist Use and Residual Gastric Content Before Anesthesia. JAMA Surgery, 2024
https://pmc.ncbi.nlm.nih.gov/articles/PMC10918573/
American Academy of Orthopaedic Surgeons, Optimal Timing for Cessation of GLP-1 Agonist Before Elective Total Hip and Knee Arthroplasty (2025 Annual Meeting)
Wegovy (semaglutide) prescribing information, DailyMed
https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f5e548d0-cc79-4c34-a3f5-e20a5b8b6564
Zepbound (tirzepatide) prescribing information, DailyMed
https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=487cd7e7-434c-4925-99fa-aa80b1cc776b
This information is educational and is not a substitute for medical advice. Talk to your prescriber and your surgical team about your specific situation.
