Dumping syndrome

People who have had stomach or weight-loss surgery can develop dumping syndrome, which causes cramping, diarrhea and, sometimes, low blood sugar.

Update Date: 20.09.2025

Overview
Symptoms
When to see a doctor
Causes
Risk factors
Diagnosis
Treatment
Alternative medicine
Self care
Preparing for your appointment

Overview

Dumping syndrome is a condition in which food moves from the stomach into the small intestine too quickly after eating, more commonly seen after certain surgeries. It's sometimes called rapid gastric emptying. Dumping syndrome most often happens after surgery on the stomach or esophagus.

Most people with dumping syndrome develop symptoms, such as stomach cramps and diarrhea, 10 to 30 minutes after eating. Other people have symptoms 1 to 3 hours after eating. And still others have both early and late symptoms.

Generally, you can help prevent dumping syndrome by changing your diet after surgery. Changes might include eating smaller meals and limiting high-sugar foods. In more-serious cases of dumping syndrome, you may need medicines or surgery.

Symptoms

Symptoms of dumping syndrome generally start within minutes after eating, especially after a meal rich in table sugar or fruit sugar. They include:

  • Feeling bloated or too full after eating.
  • Nausea.
  • Vomiting.
  • Stomach cramps.
  • Diarrhea.
  • Flushing.
  • Dizziness or lightheadedness.
  • Rapid heart rate.

Late dumping syndrome starts 1 to 3 hours after you eat a high-sugar meal. It takes time for symptoms to develop. This is because after you eat, your body releases large amounts of insulin to absorb the sugars entering your small intestine. The result is low blood sugar.

Symptoms of late dumping syndrome can include:

  • Sweating.
  • Flushing.
  • Dizziness or lightheadedness.
  • Weakness.
  • Rapid heart rate.

Some people have both early and late symptoms. And dumping syndrome can develop years after surgery.

When to see a doctor

Contact a healthcare professional if any of the following apply to you:

  • You develop symptoms that might be due to dumping syndrome, even if you haven't had surgery.
  • Your symptoms are not controlled by dietary changes.
  • You are losing large amounts of weight due to dumping syndrome. You may be referred to a registered dietitian to help you create an eating plan.

Causes

In dumping syndrome, food and gastric juices from your stomach move to your small intestine in an uncontrolled, abnormally fast manner. This is most often related to changes in your stomach associated with surgery. This includes any stomach surgery or major esophageal surgery, such as removal of the esophagus, called esophagectomy. But in rare cases, dumping syndrome can develop without a history of surgery or other obvious causes.

Stomach and pyloric valve

The stomach is a muscular sac about the size of a small melon. When eating or drinking, it expands to hold as much as a gallon of food or liquid. Once the stomach pulverizes the food, strong muscular contractions called peristaltic waves push the food toward the pyloric valve. Food then moves into the upper portion of the small intestine, called the duodenum.

Risk factors

Surgery that alters the stomach can increase the risk of dumping syndrome. These surgeries are most commonly done to treat obesity, but also are part of treatment for stomach cancer, esophageal cancer and other conditions. These surgeries include:

  • Bariatric surgery, especially gastric bypass surgery (Roux-en-Y operation) or sleeve gastrectomy, which is performed to treat morbid obesity.
  • Gastrectomy, in which a portion or all of the stomach is removed.
  • Esophagectomy, in which all or part of the tube between the mouth and the stomach is removed.
  • Fundoplication, a procedure used to treat gastroesophageal reflux disease (GERD) and hiatal hernia.
  • Vagotomy, a type of surgery to treat stomach ulcers.
  • Pyloroplasty, which is done to widen the valve to the stomach (pylorus), allowing food to pass through.

Gastric bypass surgery

Before gastric bypass, food (see arrows) enters the stomach and passes into the small intestine. After surgery, the amount of food a person can eat is reduced due to the smaller stomach pouch. Food is also redirected so that it bypasses most of the stomach and the first section of the small intestine (duodenum). Instead, food flows directly into the middle section of the small intestine (jejunum), limiting the absorption of calories.

Diagnosis

A healthcare professional may use some of the following methods to diagnose dumping syndrome.

  • Medical history and evaluation. A healthcare professional can often diagnose dumping syndrome by taking a medical history, particularly if you've had stomach surgery, and evaluating your signs and symptoms.
  • Blood sugar test. Because low blood sugar is sometimes associated with dumping syndrome, an oral glucose tolerance test may be done. This test measures your blood sugar level at the peak time of your symptoms to help confirm the diagnosis.
  • Gastric emptying test. A radioactive material is added to food to measure how quickly food moves through your stomach.

Treatment

Early dumping syndrome is likely to resolve on its own within three months. In the meantime, there's a good chance that dietary changes will ease your symptoms. If not, medicines or surgery may be recommended.

Medicines

If changes to your diet don't improve symptoms, octreotide (Sandostatin) may be prescribed. This anti-diarrheal medicine is administered by injection under the skin and can slow the emptying of food into the intestine. Possible side effects include nausea, diarrhea and fatty stools.

Talk with your healthcare team about the proper way to self-administer the medicine.

Surgery

If conservative approaches don't help, surgery may be recommended. Depending on your situation, surgical procedures to treat dumping syndrome may include reconstructing the pylorus or surgery to reverse gastric bypass surgery.

Alternative medicine

Some people use supplements such as pectin and guar gum to thicken the digestive contents and slow its progress through the intestines. If you decide to try a supplement, discuss it with your healthcare team to learn about possible side effects or interactions with other medicines you're taking.

Self care

Here are some dietary strategies that can help you maintain good nutrition and minimize your symptoms.

  • Eat smaller meals. Try eating five or six small meals a day rather than three larger ones.
  • Lie down after meals. Try lying down for 30 minutes after you eat.
  • Drink most of your fluids between meals. At first, don't drink anything for 30 to 60 minutes before and after meals.
  • Drink 6 to 8 cups (1.4 to 1.9 liters) of fluids a day. At first, limit fluid with meals to 1/2 cup (118 milliliters). Increase fluid with meals as you tolerate it.

  • Change your diet. Eat more protein, including meat, poultry, creamy peanut butter and fish, and complex carbohydrates such as oatmeal and other whole-grain foods high in fiber. Limit high-sugar foods, such as candy, table sugar, syrup, sodas and juices.

    The natural sugar in dairy products (lactose) might worsen your symptoms. Try small amounts at first, or eliminate them if you think they're causing problems. You might want to see a registered dietitian for more advice about what to eat.

  • Increase fiber intake. Guar gum and pectin in food or supplements can delay the absorption of carbohydrates in the small intestine.
  • Check with your healthcare team about drinking alcohol.

Preparing for your appointment

If you have symptoms of dumping syndrome, you're likely to first see a member of your healthcare team. You may then be referred to a doctor who specializes in treating digestive system disorders, called a gastroenterologist.

Here's some information to help you get ready for your appointment.

What you can do

  • Be aware of pre-appointment restrictions. When you make the appointment, ask if there's anything you need to do beforehand, such as restrict your diet.
  • Write down your symptoms, including any that may seem unrelated to the reason for which you scheduled the appointment.
  • Write down key personal information, including major stresses or recent life changes.
  • List all medicines, vitamins or other supplements you take, including dosage.
  • Take a family member or friend along to help you remember everything.
  • Bring your medical records about past treatment, especially stomach surgery.
  • Write down questions to ask during your appointment.

Questions to ask your doctor

For dumping syndrome, some basic questions to ask include:

  • What is likely causing my symptoms?
  • What are other possible causes?
  • What tests do I need?
  • What is the best course of action?
  • Should I see a dietitian?
  • I have other health conditions. How can I best manage them together?
  • Should I see a specialist?
  • Are there brochures or other printed material that I can take? What websites do you recommend?

Don't hesitate to ask other questions during your appointment.

What to expect from your doctor

You'll likely be asked a few questions, including:

  • Have you had stomach surgery, and if so, what kind?
  • When did your symptoms begin?
  • Have your symptoms been continuous or occasional?
  • How long after eating do your symptoms begin?
  • Do certain foods make your symptoms worse?
  • How severe are your symptoms?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?

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