Dumping syndrome (DS) occurs when the stomach empties food into the small bowel at a faster rate than normal. It is frequently related to the rapid emptying of hyperosmolar gastric content into the small bowel. Although the precise mechanism of DS is not known, dumping is a phenomenon usually caused by the destruction or bypass of the pyloric sphincter. DS can occur in post–gastric bypass patients when high levels of simple carbohydrates are ingested. The condition can also develop in people who have had esophageal surgery. Clinically significant dumping symptoms occur in about 20% of patients after pyloroplasty or distal gastrectomy. Patients younger than age 35 years or with a BMI <25 kg/m2 are more likely to be symptomatic than are older or more obese patients.1-3
It is believed that the osmotic gradient draws fluid into the intestine, and this may release one or more vasoactive hormones, such as serotonin and vasoactive intestinal polypeptide. Most people with DS develop abdominal cramps and diarrhea within 10 to 30 minutes after eating. Others experience such symptoms 1 to 3 hours after eating, and yet others experience both early and late symptoms.