Do You Have to Stop Ozempic or Zepbound Before Surgery or a Colonoscopy?

Do you have to stop your GLP-1 before surgery?

Not automatically, and not according to one fixed rule. Since the October 2024 multi-society guidance, whether you hold semaglutide, tirzepatide or another GLP-1 before a procedure is meant to be an individual decision made together by you, your procedural team, your anesthesia team and the clinician who prescribed the drug — not a blanket instruction that applies to everyone.

That is a real change from 2023, and it is why this question turns up three different answers online, all of them current-looking.

To be explicit about what this page is: general education, not medical advice. WholeHealth Hydration does not prescribe GLP-1 medications, and nothing here tells you to start, stop or change one. The people with authority to make that call are the clinician doing your procedure, the anesthesiologist sedating you, and whoever wrote your prescription — working it out with you.

Why does a weight-loss medication matter for anesthesia at all?

Because GLP-1 medications slow how fast the stomach empties, so a stomach that should be empty after a normal overnight fast sometimes isn't. The concern under sedation or general anesthesia is aspiration — stomach contents coming back up and going into the lungs.

This is on the FDA labels, not inferred. The Ozempic prescribing information states the drug delays gastric emptying and describes rare postmarketing reports of pulmonary aspiration in patients on GLP-1 receptor agonists undergoing elective procedures under general anesthesia or deep sedation who had residual gastric contents despite reported adherence to preoperative fasting. The Zepbound label carries the same warning.

Both labels also say something people skip over: the data are insufficient to tell anyone whether modifying the fasting instructions or temporarily stopping the drug reduces retained stomach contents. The FDA named the risk without claiming to know the fix.

There is measurement behind it too. In a cross-sectional study of 124 prospectively enrolled fasted patients published in JAMA Surgery in June 2024, gastric ultrasound found increased residual stomach contents in 56% of GLP-1 users compared with 19% of non-users, an adjusted prevalence ratio of 2.48. Take it for what it is: one tertiary center, 62 GLP-1 users and 62 comparison patients, adjusted for confounding statistically rather than matched patient to patient. Not proof of harm — but it is why anesthesia teams stopped treating a normal fast as automatically reassuring.

What do the anesthesia and gastroenterology societies actually recommend now?

The current reference point is the multi-society guidance published on October 29, 2024, and it does not tell everyone to stop. It was approved by five organizations — 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 — and co-published across three of their journals.

Its core position: use of these medications around a procedure should be based on shared decision-making by the patient together with the procedural, anesthesia and prescribing care teams, balancing the metabolic need for the drug against that person's individual risk. Note the third of those teams, because it is the one most often dropped — your prescriber is a decision-maker here, not someone to be routed around. Patients without elevated risk of delayed gastric emptying may continue the medication. Where there is concern about delayed emptying, the document points to a liquid diet for at least 24 hours beforehand, the approach already used before colonoscopy and bariatric surgery, rather than automatic discontinuation.

The authors are careful to call it guidance rather than an evidence-based guideline, because the evidence base is thin.

Why do you keep seeing different answers — one week, 24 hours, two weeks?

Because they come from three different kinds of document, published at different times, and the later ones did not erase the earlier ones from the internet. Here is the sequence, and what each item actually is.

• June 2023 — American Society of Anesthesiologists consensus-based guidance. A single-society document. As the 2024 multi-society document and a 2025 Cleveland Clinic Journal of Medicine review both describe it, it advised holding daily-dosed agents on the day of surgery and weekly-dosed agents for one week before — keyed to the dosing schedule, not to the person. Source of the "seven days" answer.
• October 2024 — multi-society guidance, five societies including the ASA. Individual risk assessment and shared decision-making instead of a universal hold, with a liquid diet for at least 24 hours where delayed emptying is a concern. Where a team judges discontinuation necessary, it suggests following the original ASA intervals.
• March 2025 — one study presented at the AAOS Annual Meeting. "Optimal Timing for Cessation of GLP-1 Agonist Before Elective Total Hip and Knee Arthroplasty," a retrospective analysis of TriNetX database records, reported that cessation at 14 and 30 days was not independently associated with the four anesthesia complications studied, while shorter windows were. Source of the "two weeks" answer.

Be clear about what that last item is. It is a conference presentation with an AAOS press-kit summary — one group's retrospective database analysis, comparing cessation cohorts of a few hundred patients each against 206,005 controls. Not peer-reviewed, and not a society recommendation. Pages calling it "2025 guidance" give it weight it does not carry, and it looked only at hip and knee replacement, not colonoscopy or minor procedures.

What moved between 2023 and 2024 was the judgment that a blanket hold carried its own harms. The 2024 document weighs the aspiration concern against hyperglycemia in people who need the drug, against the cost and hypoglycemia risk of bridging therapy, and says plainly that withholding it only from patients with overweight and obesity could constitute bias that should be avoided.

Is a colonoscopy or endoscopy different from surgery?

Somewhat, and the 2024 guidance covers both deliberately. Societies of endoscopists and gastroenterologists helped write it, and one of its stated aims is safe continuation of endoscopy and prevention of procedure cancellation.

The practical difference works in your favor. A colonoscopy already puts you on a clear liquid diet for roughly a day as part of bowel prep, close to what the guidance describes where delayed emptying is a concern. That does not make the medication irrelevant — sedation for endoscopy still carries aspiration risk, and the depth of sedation varies by center and by case. It means the prep may already have done part of the job, and your gastroenterologist is the one who should say so.

What if you're still increasing your dose, or still having nausea?

Those are two of the factors that move you into the higher-risk group, so say them out loud when you call. The 2024 guidance names the features that raise concern about retained stomach contents:

• Being in the escalation phase rather than on a stable maintenance dose
• Higher doses
• Weekly dosing formulations rather than daily ones
• Gastrointestinal symptoms — nausea, vomiting, abdominal pain, dyspepsia, constipation
• Conditions affecting gastric motility, such as gastroparesis, bowel dysmotility or Parkinson's disease

Feeling full hours after a small meal counts as a symptom worth reporting even if you would not have called it nausea. If you want the fuller picture on what is typical on these medications, our page on GLP-1 side effects goes through the labeled rates.

Who makes the final call, and when should you tell them?

You, the clinician doing your procedure, your anesthesia team and your prescriber make it together — that is what the 2024 guidance means by shared decision-making — and you should tell all of them at least two weeks before the date, not on the morning of.

Two weeks matters because if the team decides you should hold a weekly injection, that decision has to be made before your next scheduled dose, not after it. Morning-of disclosure is how procedures get cancelled at the door.

When you call, give them four specific things:

1. The drug name, and whether it's the injectable or oral form
2. Your current dose, and whether you're still titrating up
3. The date of your last injection
4. Any GI symptoms you have had in the past week

Tell the surgical office, the anesthesia pre-op nurse or clinic, and your prescriber. Assume none of them has the others' notes. Both FDA labels instruct clinicians to tell patients to inform their providers before any planned procedure, which means the system expects this to come from you. If they give you different answers, say so and ask them to settle it with each other — that is the conversation the guidance is asking for.

What happens to hydration when you're told clear liquids for 24 hours?

A day of clear liquids plus a bowel prep is a real fluid and electrolyte load, and prep labeling treats it as one. The SUTAB label tells clinicians to advise all patients to hydrate adequately before, during and after use, and to use the prep with caution in people on medications that may affect kidney function — diuretics, ACE inhibitors, angiotensin receptor blockers or NSAIDs.

So follow the oral fluid instructions that came with your prep, and call the office scheduling your procedure if you are vomiting, cannot keep the prep down, are lightheaded, or are not urinating. That same label tells clinicians to consider bloodwork afterward if significant vomiting or signs of dehydration develop. Those calls belong to your team, not us.

Here is the honest version of our side. We will not place an IV in someone inside their pre-procedure fasting window without their surgical or anesthesia team's explicit direction, and you should be wary of any mobile provider who would. An unplanned IV before a procedure can affect fluid status, electrolytes and anesthesia planning — their call, not ours.

Afterward is a different question. Once you have been discharged, cleared to eat and drink, and your team has no objection, hydration support is a normal service request. If you are on a GLP-1 long-term, our page on GLP-1 support IV therapy covers what that looks like outside any procedure context, and our who should skip a drip page lists the situations where the right answer is no.

So what should you actually do this week?

Call the office scheduling your procedure today and tell them you are on a GLP-1, with the drug, the dose and your last injection date. Then ask one question: "Do you want me to hold it, change my diet before the procedure, or neither?" Get the answer from them, write it down, and follow it.

Do not start, stop or change a prescribed medication because of anything you read here or anywhere else online. Do not assume the 2023 seven-day interval applies to you, and do not assume it doesn't. The guidance changed because the profession decided this should be a decision about you specifically, made with the people who can see your chart — including the clinician who prescribed the drug.

If you have questions about IV hydration after you are cleared, or about how any of this interacts with ongoing GLP-1 therapy, you can reach us and speak with a nurse. Our safety page explains how we screen, and what we decline.