GLP-1s and Surgery: The Anesthesia Risk Nobody Told You About

Sarah followed all the pre-surgery instructions.

She fasted for 12 hours before her gallbladder removal. But when the anesthesiologist intubated her, she aspirated—vomiting stomach contents into her lungs despite the long fast.

The complication added days to her hospital stay and weeks to her recovery. What nobody had asked: she'd been on Ozempic for six months.

This scenario, once rare, is becoming increasingly common as millions of patients take GLP-1 medications. The American Society of Anesthesiologists (ASA) has issued guidance, but many patients—and even some healthcare providers—aren't aware of the risks.

The Problem: Delayed Gastric Emptying

GLP-1 medications work partly by slowing how fast food leaves your stomach (gastric emptying). This is a feature, not a bug—it helps you feel full longer and reduces appetite.

But during surgery, it becomes a hazard.

Normal pre-surgery fasting: Patients fast for 6-12 hours so their stomachs are empty during anesthesia. An empty stomach prevents aspiration—accidentally inhaling stomach contents into the lungs.

With GLP-1s: Even after prolonged fasting, patients may still have food or liquid in their stomachs. One study found that 56% of GLP-1 patients still had significant gastric content after standard fasting periods.

The risk: When sedated, protective reflexes are suppressed. If there's food in your stomach, you can vomit and inhale (aspirate) that material into your lungs. Aspiration pneumonia can be severe—even life-threatening.

ASA Guidelines: When to Stop GLP-1s

The American Society of Anesthesiologists issued updated guidance in 2023 (with clarifications since). Here's the current recommendation:

Note: Guidelines continue to evolve. Follow your anesthesiologist's specific instructions.

Which Procedures Apply?

This isn't just about major surgery. The concern applies to any procedure involving sedation or general anesthesia:

• Any surgery under general anesthesia
• Colonoscopy/endoscopy (already requires bowel prep; GLP-1s add complexity)
• Dental procedures with sedation
• Outpatient procedures (same-day surgery)
• Diagnostic procedures with sedation (cardiac catheterization, bronchoscopy)

Procedures that likely don't require stopping:

• Procedures with only local anesthesia (no sedation)
• Imaging studies without sedation
• Minor office procedures

What If You Have GI Symptoms?

GLP-1 side effects like nausea, bloating, and stomach discomfort suggest even slower gastric emptying. If you're experiencing these symptoms before scheduled surgery:

• Tell your surgical team immediately
• The procedure may need to be delayed
• Extended fasting may be required
• Ultrasound may be used to check stomach contents before proceeding

The Communication Problem

Here's the frustrating reality: many surgical teams still don't routinely ask about GLP-1 medications.

Why the gap?

• GLP-1 use has exploded faster than clinical protocols have updated
• Pre-surgical questionnaires may not specifically list these medications
• Patients don't realize their weight loss medication is relevant to surgery
• Some providers lump GLP-1s with "supplements" mentally

You need to volunteer this information. Don't wait to be asked. Tell every medical professional involved in your procedure:

• The surgeon scheduling your procedure
• The pre-operative nurse
• The anesthesiologist
• The pre-surgical phone call

Emergency Surgery: What Happens

You can't always plan surgeries. If you need emergency surgery while on GLP-1s:

• Tell the team immediately what GLP-1 you take and when you last took it
• They will likely treat you as having a "full stomach" regardless of fasting status
• Rapid sequence intubation: A faster technique that minimizes aspiration risk
• Additional precautions may be taken (nasogastric tube, positioning, medications)

Emergency surgery on GLP-1s is manageable—but the team needs to know what they're dealing with.

Practical Steps for Patients

Before Any Scheduled Procedure:

1. Inform your surgical team as soon as the procedure is scheduled
2. Ask specifically about GLP-1 discontinuation timing
3. Confirm instructions in writing if possible
4. Mark your calendar for when to stop the medication
5. Report any GI symptoms (nausea, bloating) before the procedure

What to Tell the Team:

• Exact medication name (Ozempic, Wegovy, Zepbound, Mounjaro, compounded, etc.)
• Dose
• When you last took it
• How long you've been on it
• Any current GI symptoms

After Surgery: Restarting GLP-1s

After your procedure, ask your surgical team when it's safe to restart your GLP-1. General considerations:

• Wait until you're tolerating oral intake normally
• Make sure nausea/vomiting from anesthesia has resolved
• GI surgery may require longer wait times
• Coordinate with your prescribing provider

Missing a dose or two for surgery won't derail your weight loss progress. Safety comes first.

The Bottom Line

GLP-1s are revolutionary medications, but they interact with anesthesia in ways that create real risks. The good news: these risks are manageable with proper planning.

Your responsibilities:

• Tell every surgical team member that you take a GLP-1
• Don't assume they'll ask or that it's in your chart
• Follow hold instructions precisely
• Report any GI symptoms before procedures

This isn't about creating fear—it's about informed participation in your healthcare. With proper communication and planning, patients on GLP-1s have surgery safely every day.