When should the last dose of Zepbound (generic name) be given prior to a colonoscopy?

Timing of Last Zepbound Dose Before Colonoscopy

Zepbound (tirzepatide) should be discontinued 1 week (7 days) before colonoscopy to minimize the risk of inadequate bowel preparation due to delayed gastric emptying.

Critical Background on GLP-1 Receptor Agonists

• Zepbound is a GIP/GLP-1 receptor agonist that significantly delays gastric emptying, which can interfere with bowel preparation quality and increase aspiration risk during sedation
• Unlike DPP-4 inhibitors (such as Januvia), GLP-1 receptor agonists substantially affect gastric motility and must be held before colonoscopy 1

Recommended Discontinuation Timeline

• Stop Zepbound 7 days (1 week) before the scheduled colonoscopy procedure
• This timing allows for:
  • Clearance of the medication's gastric emptying effects
  • Adequate bowel preparation efficacy
  • Reduced aspiration risk during procedural sedation

Bowel Preparation Timing After Discontinuation

Once Zepbound has been appropriately discontinued, follow standard bowel preparation protocols:

• For split-dose regimen (preferred approach):

  • Begin the second portion of bowel preparation 4-6 hours before colonoscopy 2
  • Complete the preparation at least 2 hours before the procedure start 2, 3
  • This timing is critical: each additional hour between last purgative dose and colonoscopy decreases the likelihood of good preparation by 10% 2

• For afternoon procedures:

  • Same-day bowel preparation regimens are an acceptable alternative 2, 3
  • Begin drinking purgative 4-6 hours before procedure time 2
  • Complete at least 2 hours before colonoscopy start 2

Key Safety Considerations

• Aspiration risk: The American Society of Anesthesiologists recommends clear liquids up to 2 hours before sedation, but this assumes normal gastric emptying 2, 4
• Inadequate preparation risk: Delayed gastric emptying from GLP-1 agonists can compromise both bowel preparation quality and increase retained gastric contents 4
• Monitor blood glucose: Check glucose levels more frequently during the period when Zepbound is discontinued, as glycemic control may be affected 5

Post-Procedure Resumption

• Resume Zepbound after the colonoscopy once normal eating has been established
• Ensure adequate hydration before restarting the medication
• No specific kidney function monitoring is required for Zepbound resumption (unlike SGLT-2 inhibitors) 1

Common Pitfall to Avoid

• Do not treat Zepbound like a DPP-4 inhibitor: Unlike Januvia which can be safely continued through colonoscopy, GLP-1 receptor agonists like Zepbound must be discontinued due to their significant effects on gastric emptying 1