You have surgery coming up. You take GLP-1 medication. What do you need to do?
This is important. GLP-1 medications affect how anesthesia works. Your surgical team needs to know.
Here is what to expect.
Why GLP-1s Matter for Surgery
Slowed stomach emptying
GLP-1 medications slow how fast food leaves your stomach. This is great for weight loss and blood sugar control.
But it is a problem for anesthesia.
When you are under general anesthesia, your body's normal reflexes are turned off. If food is still in your stomach, it can enter your lungs. This is called aspiration. It is dangerous.
The risk
People on GLP-1s may have food in their stomach even after fasting for the recommended time before surgery.
Standard fasting rules say no food for 8 hours before surgery. But GLP-1s can keep food in your stomach for 12+ hours.
What to Tell Your Doctor
Before surgery
Tell every member of your surgical team that you take GLP-1 medication. This includes:
- Your surgeon
- Your anesthesiologist
- Your primary care doctor
- Any specialists involved in your care
Tell them:
- The name of your medication
- Your dose
- When you last took it
- How long you have been on it
Do not assume they already know. Always speak up.
During your pre-op visit
Your doctor may order an ultrasound to check if your stomach is empty before surgery. This is becoming more common for GLP-1 users.
When to Stop GLP-1 Before Surgery
Current guidelines
The American Society of Anesthesiologists recommends:
Weekly GLP-1 medications (Ozempic, Wegovy, Mounjaro, Zepbound): Stop 1 week (7 days) before surgery.
Daily GLP-1 medications: Stop on the day of surgery.
Your doctor may say something different
These are general guidelines. Your surgeon or anesthesiologist may give you different instructions based on:
- The type of surgery
- Your dose
- How long you have been on the medication
- Your digestive symptoms
- Other health conditions
Always follow your surgical team's specific instructions.
What If I Cannot Stop My Medication?
Some people cannot safely stop their GLP-1 medication. This is especially true for people with diabetes who rely on it for blood sugar control.
If you cannot stop:
- Your anesthesiologist will take extra precautions
- They may use a different anesthesia approach
- They may delay surgery if your stomach is not empty
- They may order a stomach ultrasound before proceeding
This is not a reason to cancel surgery. It just means your team needs to plan carefully.
After Surgery
When to restart
Most doctors recommend restarting your GLP-1 medication once:
- You are eating normally
- You are keeping food down
- You are no longer on strong pain medications that affect digestion
This is usually a few days to a week after surgery.
Start low if needed
If you stopped for more than 2 weeks, your doctor may recommend restarting at a lower dose. This reduces the risk of side effects.
Watch for side effects
After surgery, your body is stressed. Adding a GLP-1 medication back in can cause nausea or digestive issues.
Start slow. Eat small meals. Stay hydrated.
For more on managing side effects, see our side effects guide.
Special Considerations
Dental surgery
Even minor dental procedures may require you to stop your GLP-1. Sedation can cause the same stomach emptying issues.
Tell your dentist about your medication.
Emergency surgery
If you need emergency surgery and cannot stop your GLP-1 ahead of time, tell the emergency team immediately.
They will take extra precautions to protect your airway.
Bariatric surgery
If you are having weight loss surgery, your GLP-1 medication plan will be specific to your procedure.
Follow your bariatric surgeon's instructions carefully. They will tell you when to stop and restart.
The Bottom Line
GLP-1 medications and surgery require careful planning.
Your surgery checklist:
- Tell every doctor about your GLP-1 medication
- Ask when to stop before surgery
- Follow your surgical team's instructions exactly
- Do not restart until your doctor says it is safe
- Start at a lower dose if you stopped for more than 2 weeks
This is not something to handle on your own. Your surgical team needs to be involved from start to finish.
Medical Disclaimer
This article is for informational purposes only and does not constitute medical advice. Always follow the specific instructions provided by your surgeon and anesthesiologist regarding GLP-1 medication management before and after surgery. Guidelines may change as new research becomes available. Never stop or restart prescription medications without consulting your healthcare provider.
Know someone having surgery on GLP-1s? Share this article with them.
