Severe Dumping and Persistent Obesity in a Post-Roux-en-Y Gastric Bypass Patient With a Non-discernible Gastric Pouch and Symptomatic Improvement on Tirzepatide: A Case Report.

Rapid transit of ingested nutrients into the small bowel following gastric or esophageal surgery can trigger dumping syndrome, a recognized postoperative complication seen with particular frequency after Roux-en-Y gastric bypass (RYGB). Under normal operative conditions, RYGB constructs a proximal gastric pouch that serves to limit meal volume and pace nutrient delivery into the jejunum. This report describes a 65-year-old woman with a history of RYGB and subsequent surgical revisions who presented with debilitating postprandial symptoms consistent with dumping syndrome alongside persistent class III obesity. Upper endoscopy revealed no identifiable gastric pouch or gastric mucosa, with jejunal tissue encountered immediately distal to the esophagus. Her clinical course was notable for poor food tolerance, absent satiety, and substantial weight recidivism. After starting tirzepatide she demonstrated meaningful symptomatic relief alongside a BMI reduction from 46 to 41.9. Interpretation of this case is limited by the unavailability of operative records and the absence of objective diagnostic workup, precluding any definitive conclusions about causation. Nevertheless, the case draws attention to an uncommon postoperative anatomical configuration that appears to contribute to both severe dumping physiology and failure of weight maintenance. Additionally, the clinical response observed with tirzepatide raises the possibility of a therapeutic application in this patient population, pending more robust evidence.