For how long should semaglutide (glucagon-like peptide-1 receptor agonist) be held before general anesthesia?

Semaglutide Should Be Held for at Least 3 Weeks Before Elective General Anesthesia

For patients taking weekly semaglutide, hold the medication for at least 3 weeks (approximately three half-lives) before elective surgery to minimize the risk of pulmonary aspiration, though emerging evidence suggests even this may be insufficient in some cases. 1

The Critical Problem: Delayed Gastric Emptying Persists Despite Standard Fasting

Semaglutide significantly delays gastric emptying, creating a dangerous situation where patients have retained gastric contents despite following—and even exceeding—standard fasting guidelines. 2

• 40% of patients who stopped semaglutide within 10 days of surgery had increased residual gastric content versus only 3% of controls, demonstrating that short discontinuation periods are inadequate 3
• 24.2% of patients on semaglutide had residual gastric content compared to 5.1% of controls, even with 12+ hour fasting periods 2
• Multiple case reports document pulmonary aspiration requiring ICU admission in patients who fasted 18-20 hours and stopped semaglutide 4-6 days before surgery 2

Evidence-Based Holding Periods

Minimum Recommended Duration

• Hold weekly semaglutide for at least 3 weeks (three half-lives) before elective procedures 1
• The American Society of Anesthesiologists initially recommended 1 week, but this is now recognized as insufficient 1

Risk Stratification by Holding Period

• < 8 days: Highest risk—10-fold increased odds of retained gastric contents 4
• 8-14 days: Intermediate risk—4.6-fold increased odds of retained gastric contents 4
• > 14 days without digestive symptoms: Risk approaches baseline 4
• > 21 days with ongoing digestive symptoms: Required to normalize risk 4

When Adequate Holding Time Is Not Possible

If surgery cannot be delayed to allow 3 weeks of discontinuation, implement full stomach precautions: 1, 5

• Perform point-of-care gastric ultrasound to assess actual gastric contents 1, 5, 6
• Use rapid sequence intubation with cricoid pressure 1, 5
• Choose endotracheal intubation over supraglottic airways, as case reports show aspiration with supraglottic devices 2, 5
• Consider pre-operative metoclopramide as a prokinetic agent 1
• Treat as a "full stomach" case regardless of fasting duration 1, 7

Special Populations Requiring Extra Caution

Patients at Highest Risk

• Patients with pre-existing digestive symptoms (nausea, vomiting, dyspepsia, bloating) show significantly higher rates of gastric retention and require > 21 days discontinuation 2, 8, 4
• Patients on chronic therapy (median 57 months) demonstrate higher gastric residue rates 2
• Recently initiated therapy (within 4 weeks) may present particularly high risk 5
• Patients using semaglutide for weight loss showed 70% had solid food after 10 hours fasting in one study 5

Diabetes Management Considerations

• For weight loss indication: The risks of continuing until shortly before surgery outweigh benefits—prioritize the 3-week holding period 1
• For diabetes indication: Consult endocrinology to balance glycemic control against aspiration risk, but aspiration carries mortality risk that typically outweighs short-term glycemic concerns 1

Critical Pitfalls to Avoid

• Do not rely on standard fasting guidelines alone—they are insufficient for semaglutide patients 5
• Do not assume 4-6 days discontinuation is safe—serious aspiration events occurred at these intervals 2, 5
• Do not skip gastric ultrasound assessment when available, as clinical assessment cannot predict gastric contents in these patients 5, 3
• Do not use supraglottic airways in patients with inadequate holding periods, as aspiration has occurred during placement and removal 2, 5

The Bottom Line for Clinical Practice

Given semaglutide's one-week half-life and the evidence showing increased risk persisting beyond 14 days, the safest approach is to hold weekly semaglutide for 3 weeks before elective surgery. 1 For urgent or semi-elective cases where this is impossible, treat every patient as having a full stomach and implement all aspiration precautions, regardless of their fasting duration. 1, 5, 7