©2018 WebMD, Inc. All rights reserved. eMedicineHealth does not provide medical advice, diagnosis or treatment. See Additional Information.

Symptoms and Signs of Diarrhea

Doctor's Notes on Diarrhea Causes, Symptoms, Home Remedies, and Treatments

Diarrhea is a common condition that is characterized by frequent and loose bowel movements. Diarrhea that comes on suddenly is often due to a viral infection. Diarrhea that is persistent and lasts more than four to six weeks usually is a sign of an underlying problem with the gastrointestinal tract. Some conditions that cause chronic diarrhea include irritable bowel syndrome and inflammatory bowel disease. Other causes of diarrhea can include infections (such as salmonellosis, shigellosis, rotavirus, Norwalk virus, cholera, giardiasis, and cryptosporidiosis) food poisoning, and medication side effects.

Associated symptoms that often accompany diarrhea depend on the cause and include abdominal pain or cramping, nausea, vomiting, fever, blood in the stool, bloating, feeling the need to urgently have a bowel movement, watery stool, or pus in the stool.

Medical Author:
Medically Reviewed on 3/11/2019

Diarrhea Causes, Symptoms, Home Remedies, and Treatments Symptoms

  • Watery, liquid stools: The stools may be any color. The passage of red stools suggests intestinal bleeding and could be a sign of a more severe infection. The passage of thick, tarry black stools suggests significant bleeding in the stomach or upper portions of the intestine and is not usually caused by acute infections. The diarrhea may appear green in color, because stool passes through the intestines faster than usual.
  • Abdominal cramps: Occasionally diarrhea is accompanied with mild-to-moderate abdominal pain. Severe abdominal or stomach pain is not common and, if present, may suggest more severe disease.
  • Fever: A high fever is not common. If present, the affected person may have a more severe illness than acute diarrhea.
  • Bloating and gas
  • The urgent feeling or need to have a bowel movement
  • Dehydration: If diarrhea leads to dehydration, it is a sign of potentially serious disease.
  • Signs and symptoms of dehydration include:
    • Adults may be very thirsty and have a dry mouth.
    • The skin of older people may appear to be loose. The elderly may also become very sleepy or have behavioral changes and confusion when dehydrated.
    • Dehydrated infants and children may have sunken eyes, dry mouths, and urinate less frequently than usual. They may appear very sleepy or may refuse to eat or drink.

Diarrhea Causes, Symptoms, Home Remedies, and Treatments Causes

Viral infections cause most cases of diarrhea and are typically associated with mild-to-moderate symptoms with frequent, watery bowel movements, abdominal cramps, and a low-grade fever. Viral diarrhea generally lasts approximately 3 to 7 days.

The following are the common causes of diarrhea caused by viral infections:

  • Rotavirus is a common cause of diarrhea in infants.
  • Norovirus (for example, Norwalk virus, caliciviruses) is the most common cause of epidemics of diarrhea among adults and school-age children (for example, cruise ship infection, schools, nursing homes, day care facilities, and restaurants).
  • Adenovirus infections are common in all age groups.

Bacterial infections cause the more serious cases of diarrhea. Typically, infection with bacteria occurs after eating contaminated food or drinks (food poisoning). Bacterial infections also cause severe symptoms, often with vomiting, fever, and severe abdominal cramps or abdominal pain. Bowel movements occur frequently and may be watery and individuals may experience "explosive diarrhea" which is a very forceful, almost violent, expulsion of loose, watery stool along with gas.

The following are examples of diarrhea caused by bacterial infections:

  • In more serious cases, the stool may contain mucus, pus, or blood. Most of these infections are associated with local outbreaks of disease. Family members or others eating the same food may have similar illnesses.
  • Foreign travel is a common way for a person to contract traveler's diarrhea. (Traveler's diarrhea also may be caused by unfamiliar viruses or parasites.)
  • Campylobacter, salmonellae, and shigella organisms are the most common causes of bacterial diarrhea.
  • Less common causes are Escherichia coli (commonly called E coli) Yersinia, and listeria.
  • Use of antibiotics can lead to an overgrowth of Clostridium difficile (C diff) bacteria in the intestines.

Parasites cause infection of the digestive system by the use of contaminated water. Common parasitic causes of diarrhea include Giardia lamblia, Entamoeba histolytica, and Cryptosporidium.

Intestinal disorders or diseases including inflammatory bowel disease, irritable bowel syndrome (IBS), diverticulitis, microscopic colitis, and celiac disease, and malabsorption (trouble digesting certain nutrients) can cause diarrhea. Many of these disorders can cause the diarrhea to be yellow in color.

Reaction to certain medications can cause diarrhea including antibiotics, blood pressure medications, cancer drugs, gout medications, weight loss drugs, and antacids (especially those containing magnesium).

Intolerance or allergies to foods such as artificial sweeteners and lactose (the sugar found in milk) can cause diarrhea.

Alcohol abuse can cause diarrhea. Both binge drinking and chronic alcoholism may lead to loose stools.

Laxative abuse is one of the biggest self-induced causes of diarrhea, by taking too many laxatives, or taking them too frequently.

Diabetic diarrhea can be a complication of diabetes.

Radiation therapy or chemotherapy may cause loose stools and the diarrhea may last for up to three weeks after treatment ends.

Some cancers are more likely to cause diarrhea, including carcinoid syndrome, colon cancer, lymphoma, medullary carcinoma of the thyroid, pancreatic cancer, and pheochromocytoma.

Digestive surgery including stomach or intestinal surgery may cause diarrhea.

Running can cause diarrhea (sometimes referred to as "runner's trots"). This usually happens after longer distances over 10K or particularly hard runs.

Super Tips to Boost Digestive Health Bloating, Constipation, and More Slideshow

Super Tips to Boost Digestive Health Bloating, Constipation, and More Slideshow

To get the 20-35 grams of fiber your body needs each day, choose plant foods like cherries, grapes, crunchy bell peppers, beans, whole grains, and nuts. These help with digestion and constipation and are also good for your heart and blood sugar. Because they fill you up, you’ll eat less, which also helps if you are watching your weight.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.