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Diarrhoea (Am. diarrhea) is generally regarded as the passage of semi-liquid to water feaces upon a frequent basis. that is in excess of three of such motions per day. Generally diarrhoea as not being a disease in itself per se is a symptom of either a pathogenic agent such as a bacterium or virus. it also can becaused as "functional diarrhoea" such as from antibiotics, laxative abuse, or other conditions such as Crohn's disease and Colitis, Coeliac disease, IBS (Irritable Bowel Syndrome) or a little known condition called Habba Syndrome (from its discoverer Dr. Saad Habba of New Jersey inthe States).

As diarrhoea is generally a cleansing or scavanging mechanism as to rid the body of unwanted toxins, its real danger is that of dehydration. A simply way to combat dehydration is to drink plenty of fluids (except milk) or to either purchase a commercially avaliable rehydration solution or to make an ORS solution oneself. (one litre of clean pure drinking water -- boiled if uncertain -- with one tablespoon of salt, and eight tablespoons of sugar). In extreme cases if dehydration should persist, it is imperative to seek medical assistance immediately or go to the closest hospital for IV treatment.

Stress and anxiety


Diagram of the human gastrointestinal tract.

See also: List of causes of diarrhea

Diarrhea commonly results from gastroenteritis caused by viral infections, parasites or bacterial toxins.[1] In sanitary living conditions where there is ample food and a supply of clean water, an otherwise healthy patient usually recovers from viral infections in a few days. However, for ill or malnourished individuals diarrhea can lead to severe dehydration and can become life-threatening without treatment.[2]

Diarrhea can also be a symptom of more serious diseases, such as dysentery, cholera, or botulism, and can also be indicative of a chronic syndrome such as Crohn's disease or severe mushroom poisoning syndromes. Though appendicitis patients do not generally have violent diarrhea, it is a common symptom of a ruptured appendix. It is also an effect of severe radiation sickness.

Diarrhea can also be caused by dairy intake in those who are lactose intolerant.

Symptomatic treatment for diarrhea involves the patient consuming adequate amounts of water to replace that loss, preferably mixed with electrolytes to provide essential salts and some amount of nutrients. For many people, further treatment is unnecessary. The following types of diarrhea indicate medical supervision is required:

  • Diarrhea in infants
  • Moderate or severe diarrhea in young children;
  • Diarrhea associated with blood
  • Diarrhea that continues for more than two days;
  • Diarrhea that is associated with more general illness such as non-cramping abdominal pain, fever, weight loss, etc;
  • Diarrhea in travelers, since they are more likely to have exotic infections such as parasites;
  • Diarrhea in food handlers, because of the potential to infect others;
  • Diarrhea in institutions such as hospitals, child care centers, or geriatric and convalescent homes.

A severity score is used to aid diagnosis in children.[3]

Types of diarrhea

There are at least four types of diarrhea: secretory diarrhea, osmotic diarrhea, motility-related diarrhea, and inflammatory diarrhea.

Secretory diarrhea

Secretory diarrhea means that there is an increase in the active secretion, or there is an inhibition of absorption. There is little to no structural damage. The most common cause of this type of diarrhea is a cholera toxin that stimulates the secretion of anions, especially chloride ions. Therefore, to maintain a charge balance in the lumen, sodium is carried with it, along with water.

Osmotic diarrhea

Osmotic diarrhea occurs when too much water is drawn into the bowels. This can be the result of maldigestion (e.g., pancreatic disease or Coeliac disease), in which the nutrients are left in the lumen to pull in water. Osmotic diarrhea can also be caused by osmotic laxatives (which work to alleviate constipation by drawing water into the bowels). In healthy individuals, too much magnesium or vitamin C or undigested lactose can produce osmotic diarrhea and distention of the bowel. A person who does not have lactose intolerance can have difficulty absorbing lactose after an extraordinarily high intake of dairy products. In persons who do not have fructose malabsorption, excess fructose intake can still cause diarrhea. High-fructose foods that also have a high glucose content are more absorbable and less likely to cause diarrhea. Sugar alcohols such as sorbitol (often found in sugar-free foods) are difficult for the body to absorb and, in large amounts, may lead to osmotic diarrhea.

Motility-related diarrhea

Motility-related diarrhea is caused by the rapid movement of food through the intestines (hypermotility). If the food moves too quickly through the GI tract, there is not enough time for sufficient nutrients and water to be absorbed. This can be due to a vagotomy or diabetic neuropathy, or a complication of menstruation. Hyperthyroidism can produce hypermotility and lead to pseudodiarrhea and occasionally real diarrhea. Diarrhea can be treated with antimotility agents (such as loperamide).

Inflammatory diarrhea

Inflammatory diarrhea occurs when there is damage to the mucosal lining or brush border, which leads to a passive loss of protein-rich fluids, and a decreased ability to absorb these lost fluids. Features of all three of the other types of diarrhea can be found in this type of diarrhea. It can be caused by bacterial infections, viral infections, parasitic infections, or autoimmune problems such as inflammatory bowel diseases. It can also be caused by tuberculosis, colon cancer, and enteritis.


Generally, if there is blood visible in the stools, it is not diarrhea, but dysentery. The blood is trace of an invasion of bowel tissue. Dysentery is caused by an excess of water by a release of antidiuretic hormone from the posterior pituitary gland. Dysentery is a symptom of, among others, Shigella, Entamoeba histolytica, and Salmonella.

Infectious diarrhea

Main article: Infectious diarrhea

Infectious diarrhea is diarrhea caused by a microbe such as a bacterium, parasite, or virus.


Malabsorption is the inability to absorb food, mostly in the small bowel but also due to the pancreas.

Causes include celiac disease (intolerance to wheat, rye, and barley gluten, the protein of the grain), lactose intolerance (intolerance to milk sugar, common in non-Europeans), fructose malabsorption, pernicious anemia (impaired bowel function due to the inability to absorb vitamin B12), loss of pancreatic secretions (may be due to cystic fibrosis or pancreatitis), short bowel syndrome (surgically removed bowel), radiation fibrosis (usually following cancer treatment), and other drugs, including agents used in chemotherapy.

Inflammatory bowel disease

The two overlapping types here are of unknown origin:

  • Ulcerative colitis is marked by chronic bloody diarrhea and inflammation mostly affects the distal colon near the rectum.
  • Crohn's disease typically affects fairly well demarcated segments of bowel in the colon and often affects the end of the small bowel.

Irritable Bowel Syndrome

Main article: Irritable Bowel Syndrome

Another possible cause of diarrhea is Irritable Bowel Syndrome (IBS). Symptoms defining IBS: abdominal discomfort or pain relieved by defecation and unusual stool (diarrhea or constipation or both) or stool frequency, for at least 3 days a week over the previous 3 months.[4] IBS symptoms can be present in patients with a variety of conditions including food allergies, infective diarrhea, celiac, and inflammatory bowel diseases. Treating the underlying condition (celiac disease, food allergy, bacterial dysbiosis, etc.) usually resolves the diarrhea.[5] IBS can cause visceral hypersensitivity. While there is no direct treatment for undifferentiated IBS, symptoms, including diarrhea, can sometimes be managed through a combination of dietary changes, soluble fiber supplements, and/or medications.

It is important to note that IBS can often be confused with Giardiasis since false negative tests for giardia can result in a misdiagnoses of the actual cause, a parasitic infection.[6]

Other important causes

  • Ischemic bowel disease. This usually affects older people and can be due to blocked arteries.
  • Bowel cancer: Some (but not all) bowel cancers may have associated diarrhea. Cancer of the large intestine is most common.
  • Hormone-secreting tumors: some hormones (e.g. serotonin) can cause diarrhea if excreted in excess (usually from a tumor).
  • Bile salt diarrhea: excess bile salt entering the colon rather than being absorbed at the end of the small intestine can cause diarrhea, typically shortly after eating. Bile salt diarrhea is a bad side-effect of gallbladder removal. It is usually treated with cholestyramine, a bile acid sequestrant.
  • Celiac Disease
  • Intestinal Protozoa such as Giardiasis[6]


Chronic diarrhea can be caused by chronic ethanol ingestion.[7] Consumption of alcohol affects the body's capability to absorb water - this is often a symptom that accompanies a hangover after a binge drinking session. The alcohol itself is absorbed in the intestines and as the intestinal cells absorb it, the toxicity causes these cells to lose their ability to absorb water. This leads to an outpouring of fluid from the intestinal lining, which is in turn poorly absorbed. The diarrhea usually lasts for several hours until the alcohol is detoxified and removed from the digestive system. Symptoms range from person to person and are influenced by both the amount consumed as well as physiological differences.


In many cases of diarrhea, replacing lost fluid and salts is the only treatment needed. This is usually by mouth, (Oral rehydration therapy) or, in very severe cases, intravenously.

Diet restriction such as limiting milk has no effect on the duration of diarrhea.[8] Medicines such loperamide (Imodium) and bismuth subsalicylate (as found in Pepto Bismol and Kaopectate) may be beneficial however are contraindicated in certain situations.[9]

Evolutionary medicine

According to two researchers into evolutionary medicine, Nesse and Williams,[10] diarrhea functions as an evolved expulsion defense mechanism. As a result, if it is stopped, there might be a delay in illness recovery. They cite in support of this argument research carried out by DuPont and Hornick that was published in the Journal of the American Medical Association (JAMA)[11] showed that treating Shigella with the anti-diarrhea drug (Lomotil) caused people to stay feverish twice as long as those not so treated. The researchers indeed themselves observed that: "Lomotil may be contraindicated in shigellosis. Diarrhea may represent a defense mechanism".

See also


  1. Wilson ME (2005). Diarrhea in nontravelers: risk and etiology. Clin. Infect. Dis. 41 Suppl 8: S541–6.
  2. Alam NH, Ashraf H (2003). Treatment of infectious diarrhea in children. Paediatr Drugs 5 (3): 151–65.
  3. Ruuska T, Vesikari T (1990). Rotavirus disease in Finnish children: use of numerical scores for clinical severity of diarrhoeal episodes. Scand. J. Infect. Dis. 22 (3): 259–67.
  4. Longstreth GF, Thompson WG, Chey WD, Houghton LA, Mearin F, Spiller RC (2006). Functional bowel disorders. Gastroenterology 130 (5): 1480–91.
  5. Wangen, S. "The Irritable Bowel Syndrome Solution". page 113. 2006; Innate Health Publishing. ISBN 978-0-9768537-8-7. Excerpted with the author's permission at
  6. 6.0 6.1 Intestinal Protozoa
  7. Kasper DL, Braunwald E, Fauci AS, Hauser SL, Longo DL, Jameson JL. Harrison's Principles of Internal Medicine. New York: McGraw-Hill, 2005. ISBN 0-07-139140-1.
  8. BestBets: Does Withholding milk feeds reduce the duration of diarrhoea in children with acute gastroenteritis?.
  9. Schiller LR (2007). Management of diarrhea in clinical practice: strategies for primary care physicians. Rev Gastroenterol Disord 7 Suppl 3: S27–38.
  10. Nesse, R. M. Williams, G. C. (1994) 'Why We Get Sick: The New Science of Darwinian Medicine' (section,Evolution and healing, pp. 37-38) Vintage Books New York pp. ISBN 0-679-74674-9
  11. DuPont, H. L. Hornick, R. B. (1973) "Adverse effect of lomotil therapy in shigellosis". JAMA. 226: 1525-1528 PMID 4587313

External links

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