Home > Patients & Visitors > Health Library > Mild, Moderate, or Severe Diarrhea
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 has many causes. Stomach flu (gastroenteritis) or
food poisoning may cause severe diarrhea. Drinking
untreated water that contains the Giardia lamblia parasite can cause diarrhea that develops 1 to
4 weeks later.
Severe diarrhea increases your risk of
dehydration by causing your body to lose large amounts
of fluid quickly. Be sure to increase your intake of fluids, such as
water or a
rehydration drink, and to watch for symptoms of
Persistent diarrhea can have many causes, including dietary changes,
irritable bowel syndrome, and certain
medicines. Occasionally, persistent diarrhea can be a
symptom of a more serious condition, such as a chronic infection,
inflammatory bowel disease, a
malabsorption syndrome, or
ByHealthwise StaffPrimary Medical ReviewerWilliam H. Blahd, Jr., MD, FACEP - Emergency MedicineSpecialist Medical ReviewerH. Michael O'Connor, MD - Emergency Medicine
Current as ofMay 27, 2016
Current as of:
May 27, 2016
William H. Blahd, Jr., MD, FACEP - Emergency Medicine & H. Michael O'Connor, MD - Emergency Medicine
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