Clinical Research Directory

Inclusion Criteria: * Able to understand the study, provide written informed consent, and comply with study procedures. * History of an upper gastrointestinal surgical procedure associated with postprandial hypoglycemia performed at least one year before enrollment, including: Roux-en-Y gastric bypass (RYGB), vertical sleeve gastrectomy (VSG), Nissen fundoplication, or other upper gastrointestinal surgical procedures associated with postprandial hypoglycemia, as approved by the Principal Investigator. * Stable body weight (less than 2 kg change during the 4 weeks before screening). * History of postprandial hypoglycemia consistent with Whipple's triad:symptoms of hypoglycemia, documented blood glucose \<54 mg/dL by plasma or fingerstick glucose, resolution of symptoms after carbohydrate administration. * Able to tolerate oral nutrition. * Additional arm-specific eligibility criteria apply (e.g., only participants with RYGB who are independently scheduled for clinically indicated TORe are eligible for the TORe arm). Exclusion Criteria: * Diabetes mellitus (fasting plasma glucose ≥126 mg/dL). * Clinically significant liver, kidney, cardiovascular, or other major systemic disease that would increase study risk. * Pregnancy or breastfeeding. * Active vomiting, diarrhea, or inability to tolerate oral nutrition. * Active peptic ulcer disease. * Prior surgery, procedure, or medical condition that would substantially interfere with gastric emptying measurements or interpretation of study results. * Active psychiatric illness or eating disorder that would interfere with study participation. * Alcohol or substance abuse that would interfere with safe participation. * Participation in another interventional clinical trial that would interfere with this study. * Additional medication-specific exclusion criteria apply to participants enrolled in the Medication Module (e.g., contraindications to the study medication).