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Mild, Moderate, or Severe Diarrhea

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Topic Overview

Diarrhea is described as an increase in the frequency of bowel movements or a decrease in the consistency of stools that causes the discharge of watery, loose stools. The severity of diarrhea is determined by the size and number of stools passed within a period of time.

  • Severe diarrhea means having more than 10 loose, watery stools in a single day (24 hours).
  • Moderate diarrhea means having more than a few but not more than 10 diarrhea stools in a day.
  • Mild diarrhea means having a few diarrhea stools in a day.

Severe diarrhea has many causes. Stomach flu (gastroenteritis) orfood poisoningmay cause severe diarrhea. Drinkinguntreated waterthat contains the Giardia lamblia parasite can cause diarrhea that develops 1 to 4 weeks later.

Severe diarrhea increases your risk ofdehydrationby causing your body to lose large amounts of fluid quickly. Be sure to increase your intake of fluids, such as water or arehydration drink, and to watch for symptoms of dehydration.

Persistent diarrhea can have many causes, including dietary changes, stress,irritable bowel syndrome, and certainmedicines. Occasionally, persistent diarrhea can be a symptom of a more serious condition, such as a chronic infection,inflammatory bowel disease, amalabsorption syndrome, orcolorectal cancer.

Related Information


ByHealthwise Staff
Primary Medical ReviewerWilliam H. Blahd, Jr., MD, FACEP - Emergency Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine

Current as ofNovember 20, 2017

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