Question: What are the symptoms of dumping syndrome?
Answer: The symptoms of early and late dumping syndrome are different. Symptoms may vary from person to person.

Early dumping syndrome

Symptoms of early dumping syndrome occur within 30 minutes after you eat a meal. You may have digestive symptoms, such as

diarrhea
feeling uncomfortably full orbloated
nausea
pain and cramping in yourabdomen
stomach“growling” or rumbling sounds

Other symptoms of early dumping syndrome may include

feeling light-headed or fainting
feeling tired or needing to lie down
flushing, or reddening of your face, neck, or upper chest
having a fast or irregular heartbeat
headache
sweating

Symptoms of early dumping syndrome may include pain in your abdomen and feeling tired or needing to lie down.

Late dumping syndrome

Symptoms of late dumping syndrome occur 1 to 3 hours after you eat a meal. The symptoms of late dumping syndrome are caused by low blood glucose, also called low blood sugar or hypoglycemia. Symptoms of late dumping syndrome may include

feeling light-headed or fainting
feeling shaky or jittery
feeling tired
having a fast or irregular heartbeat
trouble concentrating
sweating
weakness
Question: What causes dumping syndrome?
Answer: Rapid gastric emptying, a condition in which food moves too quickly from your stomach to your duodenum, causes dumping syndrome.

Your digestive tract makes and releases hormones that control how your digestive system works. When food moves too quickly from your stomach to your duodenum, your digestive tract releases more hormones than normal. Fluid also moves from your blood stream into your small intestine. Experts think that the excess hormones and movement of fluid into your small intestine cause the symptoms of early dumping syndrome.

Experts also think that these excess hormones may cause your pancreas to produce too much insulin. Too much insulin can lead to low blood glucose 1 to 3 hours after a meal, causing the symptoms of late dumping syndrome.

Causes of rapid gastric emptying

The most common cause of rapid gastric emptying and dumping syndrome is surgery of the stomach or esophagus. Types of surgery that may lead to dumping syndrome include

weight-loss surgery, also called metabolic and bariatric surgery, such as gastric bypass surgery and gastric sleeve surgery. These operations help people lose weight.
esophagectomy, which is surgery to remove part of the esophagus. Doctors use this surgery to treat problems of the esophagus, such asesophageal cancerandBarrett’s esophagus.
fundoplication, which is surgery to sew the top of the stomach around theesophagus. Doctors use this surgery to treatgastroesophageal reflux diseaseandhiatal hernia.
gastrectomy, which is surgery to remove all or part of the stomach. Doctors use this surgery to treatstomach cancerandpeptic ulcers.
vagotomy, which is surgery to cut thevagus nervein the stomach so that the stomach makes less acid. Doctors use this surgery to treat peptic ulcers.

Rapid gastric emptying sometimes occurs in people who have not had stomach surgery. For example, rapid gastric emptying may occur in people who have

recently developeddiabetes, especiallytype 2 diabetes
pancreatic exocrine insufficiency, a condition in which the pancreas doesn’t make enough of certainenzymes, causing problems withdigestion
duodenal ulcers
Zollinger-Ellison syndrome

In some cases, a person has rapid gastric emptying and dumping syndrome but the cause is unknown.