Diarrhea is loose, watery, and frequent stools. Diarrhea is considered long-term (chronic) when you have had loose or frequent stools for more than 4 weeks.


Diarrhea in infants and children (especially under age 3) can caused dangerous dehydration very quickly.

Diarrhea in adults is usually mild and goes away quickly without complications.


The most common cause of diarrhea is viral gastroenteritis, or the stomach flu. This is a mild viral infection that goes away on its own within a few days.

Eating or drinking contaminated food or water can also lead to diarrhea. Such common causes of diarrhea include:

Certain medications may also cause diarrhea, including:

  • Certain antibiotics
  • Chemotherapy
  • Laxatives containing magnesium

Diarrhea may also be caused by certain medical conditions, including:

Less common causes of diarrhea include:

Home Care

It is important to drink plenty of fluids to prevent dehydration. Dehydration means your body does not have the proper amount of water and fluids. Dehydration can be especially dangerous for infants and young children and people who live in a hot climate.

Signs of severe dehydration include:

  • Decreased urine (fewer wet diapers in infants)
  • Dry mouth
  • Sunken eyes
  • Few tears when crying

Children with diarrhea should be given fluids only for the first 4 to 6 hours.

  • Try 2 tablespoons (1 ounce) of fluid every 30 to 60 minutes.
  • Brands such as Pedialyte can be helpful. Do not water down these fluids.
  • Pedialyte popsicles are also available.
  • Watered-down fruit juice or broth may also help.

If you are breastfeeding your infant, continue to do so.

If you are using formula, use it at half strength for 2 to 3 feedings after the child's diarrhea starts. You can use the regular amount of formula after this.

Adults and older children who have diarrhea may feel better by following these steps:

  • Drink 8 to 10 glasses of clear fluids every day. Water is best.
  • Drink at least 1 cup of liquid every time you have a loose bowel movement.
  • Eat small meals throughout the day, instead of 3 big meals.
  • Eat salty foods, such as pretzels, soup, and sports drinks.
  • Eat high potassium foods, such as bananas, potatoes without the skin, and watered-down fruit juices.
  • Get plenty of rest.

Avoid over-the-counter antidiarrhea medications unless instructed to use them by your doctor. Certain infections can be made worse by these drugs.

If you have a chronic form of diarrhea, such as is caused by irritable bowel syndrome, try adding bulk to your diet to thicken your stool and regulate bowel movements. Such foods include fiber from whole-wheat grains and bran. Psyllium-containing products such as Metamucil or similar products can also add bulk to stools and help solidify them.

When to Contact a Medical Professional

Call for an appointment with your health care provider if you have:

  • Blood or pus in your stools
  • Black stools
  • Stomach pain that does not go away after a bowel movement
  • Symptoms of dehydration (thirst, dizziness, lightheadedness)
  • Diarrhea with a fever above 101°F (100.4 °F in children)
  • Recently traveled to a foreign country and developed diarrhea

Also call your doctor if:

  • The diarrhea gets worse or does not get better in 2 days for an infant or child, or 5 days for adults
  • A child over 3 months old has been vomiting for more than 12 hours; in younger babies, call as soon as vomiting or diarrhea begins

What to Expect at Your Office Visit

Your doctor perform a physical exam and ask you questions about your medical history and symptoms, including:

  • When did your diarrhea start?
  • What is the color and consistency of your stool?
  • Do you have blood in your stool?
  • Are you passing large amounts of mucus with your stool?
  • What other symptoms do you have?
  • Do you have abdominal pain or severe cramping with the diarrhea?
  • Do you have fever or chills?
  • Are any other people in your house sick?
  • Have you recently traveled out of the country?
  • Have you possibly been exposed to unpurified water or spoiled food?
  • What makes your pain worse? Stress? Specific foods?
  • Have you had abdominal surgery?
  • Have you taken antibiotics recently?
  • What medications do you take? Any recent changes to your medications?
  • Do you drink coffee? How much?
  • Do you drink alcohol? How much? How often?
  • Do you smoke? How much each day?
  • Are you on a special diet?

Laboratory tests may be done on your stools to determine the cause of your diarrhea. If there are signs of dehydration in addition to the diarrhea, your doctor may order:


Over-the-counter supplements that contain healthy bacteria, called probiotics, may help prevent diarrhea associated with antibiotics. Yogurt with active or live cultures is a good source of these healthy bacteria.

The following healthy steps can help you prevent illnesses that cause diarrhea:

  • Wash your hands often, especially after going to the bathroom and before eating.
  • Use alcohol-based hand gel frequently.
  • Teach children to not put objects in their mouth.

When traveling to underdeveloped areas, follow the steps below to avoid diarrhea:

  • Drink only bottled water and do not use ice, unless it is made from bottled or purified water.
  • Do NOT eat uncooked vegetables or fruits that do not have peels.
  • Do NOT eat raw shellfish or undercooked meat.
  • Do NOT consume dairy products.

Alternative Names

Stools - watery; Frequent bowel movements; Loose bowel movements


Schiller RL, Sellin JH. Diarrhea. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 15.

Semrad CE, Powell DW. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders; 2007:chap 143.

Update Date: 2/16/2012

Reviewed by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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