The Short Answer
- Not always. The October 2024 US multi-society guidance says many people can keep taking their GLP-1 before a planned surgery or scope.
- Your care team decides. They weigh your stomach symptoms, your dose and your health. Do not stop on your own.
- Tell everyone. Every GLP-1 drug label now asks you to tell your providers before any planned surgery or procedure.
- Follow their eating rules exactly. You may be asked to drink only liquids for at least a day before.
If you take a GLP-1 medication like Wegovy, Ozempic, Zepbound, Mounjaro or Foundayo, and you have a surgery or a scope coming up, you may have heard you must stop it first. That advice is out of date for many people. Here is what the experts and the drug labels say now, where they disagree, and what to ask before your procedure.
Why GLP-1 Drugs Matter Under Anesthesia
GLP-1 drugs slow down how fast food leaves your stomach. That is part of how they work. Food stays in your stomach longer, so you feel full longer.
That same effect can cause trouble when you are put to sleep. Under general anesthesia or deep sedation, the reflexes that keep food down switch off. If your stomach still has food in it, some can come back up and get into your lungs. Doctors call this aspiration. It is rare, but it can cause a serious lung infection.
Fasting before surgery is meant to empty your stomach. The problem is that some people on these drugs still have food in their stomach even after fasting as told. The drug labels say there have been "rare postmarketing reports" of aspiration in people who had food left in the stomach "despite reported adherence to preoperative fasting recommendations." In plain words: rare cases, reported after the drugs went on sale, in people who said they had fasted correctly.
What the Drug Labels Say
A warning called "Pulmonary Aspiration During General Anesthesia or Deep Sedation" first appeared on GLP-1 labels in November 2024. Every current GLP-1 label we checked carries it, including Wegovy (shot and pill), Ozempic, Rybelsus, Mounjaro, Zepbound, Saxenda, Victoza and Foundayo.
The labels do two things. They ask you to "inform healthcare providers prior to any planned surgeries or procedures" if you take the drug. And they say the data are not good enough to know whether stopping the drug for a while would lower the risk. No label tells you to stop the drug before surgery. That choice is left to your care team.
What the Experts Say, and Where They Disagree
The advice has shifted since 2023, and expert groups do not all agree. Here is what each one says. The ASA is the American Society of Anesthesiologists, and the AGA is the American Gastroenterological Association. The first three are US groups. The last is UK guidance, shown for comparison; it does not replace the US advice.
| Source | Type | What it says |
|---|---|---|
| ASA June 2023 | TypeSingle-society guidance | What it says"Consider holding" daily GLP-1s on the day of the procedure, and weekly ones a week before. |
| Five US groups October 2024 | TypeJoint guidance from five groups | What it saysThe drug "may be continued" for people without a higher risk of a slow stomach. Decide together with your care teams. |
| AGA November 2023 | TypePractice update on scopes | What it saysFound "no data to support all patients stopping" before a planned scope. A liquid diet the day before is an option instead. |
| Eight UK groups January 2025 | TypeUK expert consensus (written for UK practice) | What it saysPatients "should continue these drugs before surgery," with a full risk check and steps to lower the risk. |
The October 2024 guidance was approved by the AGA Institute, 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 ASA formally "affirmed the value" of it. The ASA's own 2023 page now points readers to it. (Multi-society guidance, 2024; ASA, 2023.)
One thing all of them share: the evidence is thin. The 2024 document calls itself "guidance, and not an evidence-based guideline," and says "little evidence exists to guide the best approach." The ASA's 2023 advice was based on a handful of case reports. So when your team makes a call, they are using judgment, not a proven rule.
Who Has a Higher Risk
The 2024 guidance lists things that make it more likely your stomach is still full at surgery time:
- You are still raising your dose, rather than staying on a steady dose
- You are on a higher dose
- You take a weekly shot rather than a daily drug, since stomach side effects are more common with weekly forms
- You have stomach symptoms such as nausea, vomiting, belly pain, indigestion or constipation
- You have another condition that slows your gut, such as gastroparesis (a stomach that empties too slowly) or Parkinson's disease
If none of these fit you, the 2024 guidance says you may be able to keep taking your drug. If some do, your team may still let you keep taking it, but plan extra steps.
What Your Team Can Do Instead of Stopping the Drug
- A liquid diet for at least 24 hours before the procedure. The 2024 guidance says this "can be utilized" when there is concern your stomach is slow. Liquids leave the stomach faster than solid food.
- A quick stomach ultrasound just before the procedure to see whether it is empty. Not every hospital can offer this.
- A safer anesthesia plan that protects your airway if your stomach may be full.
- Checking you on the day. The guidance says everyone should be asked about stomach symptoms the morning of the procedure. If you are vomiting or bloated, a planned procedure may be moved.
If Your Team Decides to Pause the Drug
Sometimes the team will decide a pause is safer. The 2024 guidance says the right length of a pause "is unknown." When a pause is chosen, it falls back on the ASA's 2023 approach: skip a daily drug on the day of surgery, and hold a weekly drug for a week before. Your team may change this for you. Do not work out your own pause.
Weekly drugs last a long time in the body. How long depends on the drug, not just on how often you take it. The table below uses each drug's FDA label. "Half-life" means the time it takes for half of the drug to leave your body.
| Drug | How often you take it | Half-life (from the label) |
|---|---|---|
| Wegovy, Ozempic (semaglutide shot) | How oftenOnce a week | Half-lifeAbout 1 week |
| Wegovy pill, Rybelsus (semaglutide pill) | How oftenOnce a day | Half-lifeAbout 1 week |
| Zepbound, Mounjaro (tirzepatide) | How oftenOnce a week | Half-lifeAbout 5 days (Zepbound's label: 5 to 6 days) |
| Foundayo (orforglipron pill) | How oftenOnce a day | Half-lifeAbout 29 to 49 hours |
| Saxenda, Victoza (liraglutide) | How oftenOnce a day | Half-lifeAbout 13 hours |
Note the semaglutide pill. You take it every day, but it stays in your body as long as the weekly shot. That is one reason the plan should come from your team, not from a rule of thumb.
Who Should Not Stop on Their Own
- People with type 2 diabetes. Stopping a GLP-1 can make blood sugar climb. The 2024 guidance says any pause should be weighed against the risk of high blood sugar. If you also take insulin or other diabetes drugs, ask who will manage them around surgery.
- Anyone who has not talked to their team yet. A pause you choose on your own may not match the plan your surgeon and anesthesia team make.
- Anyone tempted to stop for good. A short, planned pause for a procedure is not the same as quitting. If you are thinking about stopping long term, read what happens when you stop GLP-1 medications first.
Colonoscopy and Endoscopy
The same concern applies to scopes done under sedation. That includes an upper endoscopy (a camera passed down into the stomach) and a colonoscopy. Food left in the stomach can make an upper scope harder and raises the aspiration risk if you are sedated.
For colonoscopy, there is a second question: do these drugs make the bowel prep work less well? Studies disagree. In a 2025 review of five studies of adults having a colonoscopy, people on GLP-1s had about twice the odds of a poor prep. A 2026 review of six studies found no statistically significant difference. Two other recent reviews also found more poor preps. These reviews pooled studies that watched patients rather than testing a change, and none showed that pausing the drug fixes the prep.
So tell the doctor doing your scope that you take a GLP-1. Ask exactly what to eat, drink and take in the days before. Do not assume the standard prep sheet covers your medicine. (AGA, 2023; prep reviews: Am J Gastroenterol 2025, Gastrointest Endosc 2026.)
Questions to Ask Your Care Team
- Should I keep taking my GLP-1 before this procedure, or pause it? If I pause, when exactly is my last dose?
- Do I need a liquid diet before? For how long, and what counts as a liquid?
- What should I do if I feel sick, bloated or full on the morning of the procedure?
- Will you check my stomach with an ultrasound, or change the anesthesia plan?
- If I have diabetes, who manages my blood sugar and my other diabetes drugs around surgery?
- When can I restart, and at what dose?
Bring the name of your drug, your dose and the day you last took it. Tell your surgeon, your anesthesia team and the clinic that prescribes your GLP-1. New to talking with doctors about these drugs? Our guide on how to talk to your doctor about GLP-1 medications can help. Slow digestion also explains many everyday GLP-1 side effects.
Frequently Asked Questions
Does a GLP-1 affect anesthesia?
The concern the labels and the guidance describe is your stomach. GLP-1s slow it down, so food may still be there when you are put to sleep. That raises the rare risk of food getting into your lungs. That is why every label asks you to tell your providers before a planned procedure.
Can I have surgery while taking a GLP-1?
Yes. Under the October 2024 US guidance, many people can keep taking their GLP-1 before planned surgery if they do not have a higher risk of a slow stomach. Your care team makes the final call.
How long does a GLP-1 stay in your system?
It depends on the drug. Semaglutide, as a shot or a pill, has a half-life of about one week, and the Wegovy label says it stays in the blood for about 5 to 7 weeks after the last 2.4 mg or 7.2 mg shot, or the last 25 mg pill. Tirzepatide's half-life is about 5 days, Foundayo's about 29 to 49 hours, and liraglutide's about 13 hours.
Can I take Ozempic before a colonoscopy?
Ask the doctor doing the colonoscopy. The AGA found no data to support everyone stopping before a planned scope, and suggested a liquid diet the day before as an option. Follow the prep and medicine instructions your doctor gives you.
What if I forgot to mention it and surgery is tomorrow?
Call the surgery or anesthesia team today. Flagging it late is far better than not flagging it. They can change your eating plan or how they put you to sleep.
What about emergency surgery?
There is no time to plan a pause. Make sure the team knows you take a GLP-1, so they can treat your stomach as if it may be full.
The Bottom Line
You may not need to stop your GLP-1 before a procedure, but that is your care team's decision, not yours to make alone. Tell every provider which drug you take, your dose and your last dose. Follow their eating rules exactly. Never stop a diabetes drug on your own.
Want a GLP-1 provider who can help plan around a procedure? Browse GLP-1 clinics by state or search the directory, then send the clinic a question through its listing.
Sources
- Clinical guidance: Kindel TL et al., Multisociety Clinical Practice Guidance for the Safe Use of GLP-1 Receptor Agonists in the Perioperative Period, Surgical Endoscopy, October 2024. Full text
- Clinical guidance: American Society of Anesthesiologists, consensus-based guidance on preoperative management of patients on GLP-1 agonists, June 29, 2023. ASA
- Clinical guidance: American Gastroenterological Association, rapid clinical practice update on GLP-1 drugs and endoscopy, November 2023. AGA
- Clinical guidance: El-Boghdadly K et al., UK multi-society consensus on GLP-1 drugs and surgery, Anaesthesia, 2025. Full text
- FDA labels (DailyMed): Wegovy, Ozempic, Rybelsus, Mounjaro, Zepbound, Saxenda, Victoza, Foundayo
- Review: Beran A et al., GLP-1 drugs and bowel preparation, American Journal of Gastroenterology, 2025 (5 studies). Abstract
- Review: Ahmed Z et al., GLP-1 drugs and bowel preparation, Gastrointestinal Endoscopy, 2026 (6 studies). Abstract
This article explains published guidance. It is not medical advice. Your own surgeon, anesthesia team and prescriber should decide what is right for you.
Updated October 2026: Rewrote this guide against the current FDA labels and the published guidance. Corrected the 2023 ASA advice, which said to "consider holding" the drug, not to stop it. Corrected the liquid diet to "at least 24 hours" as an option when there is concern about a slow stomach, not a set rule. Removed an unsupported claim that holding the drug did more harm than good, and an unsourced claim about weight regain during a pause. Added the November 2024 label warning, the 2025 UK consensus (UK guidance, which advises continuing these drugs), Foundayo, the Wegovy pill, the bowel prep studies, and questions to ask your care team.