Unexpected Residual Gastric Contents in a Patient After Holding Semaglutide After Standard Fasting Guidelines: A Case Report.

A 58-year-old man scheduled for an elective upper endoscopy followed standard preprocedural fasting guidelines and withheld one weekly dose of semaglutide, a glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-1 RA). Despite these measures, substantial residual gastric contents led to procedure cancelation. Notably, the same patient previously underwent a combined upper endoscopy and colonoscopy after withholding an identical semaglutide weekly dose, with no residual gastric contents were observed. This case suggests that adherence to standard preprocedural recommendations alone may not reliably prevent residual gastric contents in patients receiving GLP-1 RAs, and that a 24-hour liquid diet may be necessary.