Health Topic

Diarrhea

Diarrhea can range from mild to severe and can be dangerous in children. Find out what you can do to treat symptoms and when to call your doctor.

Reviewed Reviewed by a registered pharmacistGeneral information

Also called: Dysentery · The runs · The trots

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Diarrhea

Diarrhea is loose, watery stools (bowel movements). You have diarrhea if you have loose stools three or more times in one day. Acute diarrhea is diarrhea that lasts a short time. It is a common problem. It usually lasts about one or two days, but it may last longer. Then it goes away on its own.

Diarrhea lasting more than a few days may be a sign of a more serious problem. Chronic diarrhea -- diarrhea that lasts at least four weeks -- can be a symptom of a chronic disease. Chronic diarrhea symptoms may be continual, or they may come and go.

The most common causes of diarrhea include:

  • Bacteria from contaminated food or water
  • Viruses such as the flu, norovirus, or rotavirus . Rotavirus is the most common cause of acute diarrhea in children.
  • Parasites, which are tiny organisms found in contaminated food or water
  • Medicines such as antibiotics, cancer drugs, and antacids that contain magnesium
  • Food intolerances and sensitivities, which are problems digesting certain ingredients or foods. An example is lactose intolerance.
  • Diseases that affect the stomach, small intestine, or colon, such as Crohn's disease
  • Problems with how the colon functions, such as irritable bowel syndrome

Some people also get diarrhea after stomach surgery, because sometimes the surgeries can cause food to move through your digestive system more quickly.

Sometimes no cause can be found. If your diarrhea goes away within a few days, finding the cause is usually not necessary.

People of all ages can get diarrhea. On average, adults In the United States have acute diarrhea once a year. Young children have it an average of twice a year.

People who visit developing countries are at risk for traveler's diarrhea. It is caused by consuming contaminated food or water.

Other possible symptoms of diarrhea include:

  • Cramps or pain in the abdomen
  • An urgent need to use the bathroom
  • Loss of bowel control

If a virus or bacteria is the cause of your diarrhea, you may also have a fever, chills, and bloody stools.

Diarrhea can cause dehydration, which means that your body does not have enough fluid to work properly. Dehydration can be serious, especially for children, older adults, and people with weakened immune systems.

Although it is usually not harmful, diarrhea can become dangerous or signal a more serious problem. Contact your health care provider if you have:

  • Signs of dehydration
  • Diarrhea for more than 2 days, if you are an adult. For children, contact the provider if it lasts more than 24 hours.
  • Severe pain in your abdomen or rectum (for adults)
  • A fever of 102 degrees or higher
  • Stools containing blood or pus
  • Stools that are black and tarry

If children have diarrhea, parents or caregivers should not hesitate to call a health care provider. Diarrhea can be especially dangerous in newborns and infants.

To find the cause of diarrhea, your health care provider may:

  • Do a physical exam
  • Ask about any medicines you are taking
  • Test your stool or blood to look for bacteria, parasites, or other signs of disease or infection
  • Ask you to stop eating certain foods to see whether your diarrhea goes away

If you have chronic diarrhea, your health care provider may perform other tests to look for signs of disease.

Diarrhea is treated by replacing lost fluids and electrolytes to prevent dehydration. Depending on the cause of the problem, you may need medicines to stop the diarrhea or treat an infection.

Adults with diarrhea should drink water, fruit juices, sports drinks, sodas without caffeine, and salty broths. As your symptoms improve, you can eat soft, bland food.

Children with diarrhea should be given oral rehydration solutions to replace lost fluids and electrolytes.

Two types of diarrhea can be prevented - rotavirus diarrhea and traveler's diarrhea. There are vaccines for rotavirus. They are given to babies in two or three doses.

You can help prevent traveler's diarrhea by being careful about what you eat and drink when you are in developing countries:

  • Use only bottled or purified water for drinking, making ice cubes, and brushing your teeth
  • If you do use tap water, boil it or use iodine tablets
  • Make sure that the cooked food you eat is fully cooked and served hot
  • Avoid unwashed or unpeeled raw fruits and vegetables

It sits within Digestive System and Symptoms.

The lead U.S. institute for this subject is the National Institute of Allergy and Infectious Diseases.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Diarrhea

1,195 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

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Diagnosis and Tests

Treatments and Therapies

Prevention and Risk Factors

Related Issues

Genetics

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Diarrhea. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Diarrhea, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.