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Dumping syndrome

Dumping syndrome is a group of symptoms that develops when food moves too fast from the stomach into the small intestine. It may also be called rapid gastric emptying.

Causes

Dumping syndrome can develop after surgery to remove part or all of the stomach. The pylorus is the narrow, bottom part of the stomach near the small intestine. This area includes the pyloric valve, or sphincter, which is a ring of muscle that allows the contents of the stomach to empty into the duodenum. The duodenum is the first part of the small intestine. During any surgery on the stomach, the pylorus may be bypassed, damaged or removed. As a result, food moves into the duodenum at a faster rate.

Symptoms

Symptoms of dumping syndrome can vary depending on what you eat. For example, dumping syndrome may be worse after you eat foods with high carbohydrate, or sugar, content.

Symptoms also vary if they develop soon after you eat or later. Early dumping syndrome occurs 15–60 minutes after you eat. Late dumping syndrome occurs 1–3 hours after you eat.

If symptoms get worse or don’t go away, report them to your doctor or healthcare team without waiting for your next scheduled appointment.

Early dumping syndrome

With early dumping syndrome, the stomach releases undigested food into the duodenum very quickly. The small intestine pulls in fluid from surrounding tissues and blood vessels. This leads to:

  • bloating
  • abdominal cramping
  • diarrhea
  • sweating
  • dizziness
  • early satiety, which is feeling full after eating only a small amount of food
  • nausea and vomiting
  • flushing
  • palpitations, which means that your heart is beating very hard or fast or not beating regularly
  • headache
  • light-headedness

Late dumping syndrome

Similar to early dumping syndrome, undigested food is released into the small intestine very quickly. The body quickly absorbs carbohydrates and the blood sugar level rises. The body responds by releasing insulin, which causes a drop in blood sugar level, or hypoglycemia. This leads to:

  • sweating
  • shakiness
  • hunger
  • difficulty concentrating
  • feeling less alert

Diagnosis

Your doctor will try to find the cause of dumping syndrome. You may be asked to make note of symptoms and when they develop. You may also need to have the following tests:

  • glucose challenge, or tolerance, test
  • endoscopy
  • upper gastrointestinal (GI) series, or barium swallow

A glucose challenge test is used to see how your body reacts to glucose, a type of sugar that is normally found in your blood. You drink a sugary solution. About 1 hour later, your blood sugar level is measured. During this time you will make note of any symptoms you have.

Find out more about these tests and procedures.

Managing dumping syndrome

Once the extent of dumping syndrome is known, your healthcare team can suggest ways to manage it. This may include the following measures.

Dietary changes

Eat small meals throughout the day rather than 3 larger meals. Eat slowly and chew well.

Eat a lower-carbohydrate diet or eat carbohydrates as part of a meal rather than by themselves. Increase how much protein you eat. This will help keep your energy up.

Limit how much you drink with a meal. This will help lower the volume in the stomach and lower the chance of triggering the syndrome.

Avoid foods that contain a lot of sugar. Don’t eat chocolate or peppermint. Avoid or have only small amounts of milk because these foods are usually not well tolerated.

Try lying down for 30 minutes after a meal to help delay the stomach emptying its contents. Not eating or drinking after 7:00 p.m. or 8:00 p.m. may also help.

Slowly increase the amount of fibre in your diet to help reduce late dumping syndrome. Fibre binds with water to help form stool and slows the absorption of sugars in the body.

Medicines

If making changes to your diet doesn’t help you manage dumping syndrome, your healthcare team may prescribe medicines.

Acarbose (Precose) is a drug that interferes with how your body absorbs carbohydrate. It is given to control blood sugar levels after a meal and help relieve the symptoms of late dumping syndrome.

Octreotide (Sandostatin, Sandostatin LAR) is a drug that slows how quickly the stomach empties its contents into the small intestine. It is given to limit how much insulin the body releases. It helps control symptoms of both early and late dumping syndrome.

Surgery

Some people may need surgery to change how food moves through the gastrointestinal (GI) tract. Changing your diet and medicines will be tried first. Surgery is only done if these don’t relieve the symptoms of dumping syndrome.

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