The Centers for Disease Control and Prevention (CDC) defines chronic (constant) diarrhea as diarrhea that lasts for a period of two weeks or more. The site states that for those who are healthy, it is a mere inconvenience. For those who have a weak immune system, however, it can be a sign of a life-threatening illness.
Parasites
The CDC and Mayo Clinic agree that parasites and bacteria are causes of chronic diarrhea. They are transmitted to your body via contaminated food and water, and are commonly found in underdeveloped countries that do not have advanced filtration systems.
The most common bacteria responsible for chronic diarrhea include campylobacter, salmonella, shigella, E. coli and cholera, while the most common parasites include Giardia lamblia, cryptosporidium, microsporidia and Entamoeba.
Medications
Certain medications may cause diarrhea, and according to the Mayo Clinic, the most common medications responsible for this are antibiotics. This particular type of medication destroys not only the bad bacteria in your body, but the good as well. Because of this, the natural balance of bacteria in your intestines is thrown off, resulting in diarrhea. In some cases, the disturbance can lead to an infection with a bacteria--Clostridium difficile. This bacterial infection in your intestines may also result in chronic diarrhea.
Irritable Bowel Syndrome (IBS)
Jackson Siegelbaum Gastroenterology, specialists in diseases of the digestive system, state that IBS is a digestive disorder resulting in both chronic diarrhea and constipation. It occurs when the intestines do not contract as they should--in a smooth, rhythmic manner. Instead, the contractions are exaggerated, resulting in chronic diarrhea. If the contractions are slow, constipation occurs.
Diseases
Diseases of the bowel are yet another cause of chronic diarrhea. The Crohn's and Colitis Foundation of America (CCFA) state that crohn's disease and ulcerative colitis, a related bowel disease, belong to a group of diseases referred to as inflammatory disease (IBD).
Crohn's disease is a chronic, or ongoing disease, primarily affecting the small intestine and/or colon, although it can affect and cause inflammation in any part of the gastrointestinal tract (GI) from the mouth to anus.
It is estimated that one million Americans have IBD, with these numbers evenly divided between crohn's disease and ulcerative colitis. Both of these are serious medical conditions for which there is no cure, however treatments are available. Those diagnosed with either must be monitored very carefully, and as Jackson Siegelbaum Gastroenterlogy states, are a perfect example of why the causes of chronic diarrhea be known.
