Causes of Secretory Diarrhea

Secretory diarrhea is a common form of diarrhea that results when the digestive system cannot absorb water properly causing abnormal loss of water through the bowels. In healthy humans, large amounts of water are secreted into the small intestine lumen, but the majority is absorbed before it gets to the large intestine. When the amount of secretion exceeds the amount of absorption, the balance is disrupted resulting in diarrhea. Secretory diarrhea is common throughout the world and is caused by a number of diseases, conditions and bacterial infections.

Cholera

• Although the disease has been wiped out in most of the developed world, cholera is a still a major cause of secretory diarrhea in places that lack proper public hygiene or medical care. In cholera victims, the responsible organism vibrio cholerae produces the harmful cholera toxin that activates the adrenal cyclase. This disrupts proper absorption of water by opening the chloride channels responsible for releasing water from the crypts. In essence, your digestive system produces excess amounts of water that cannot be absorbed properly. Cholera also affects the enteric nervous system to stimulate independent secretion of water.

Bacterial Toxins

• There are dozens of other bacterial toxins besides cholera that cause secretory diarrhea, including the infamous food-related toxin E-coli. These work in much the same way as cholera and can be deadly without aggressive measures to maintain adequate hydration. Bacterial toxins are often found in meat that is undercooked or prepared in such a way that bacteria is able to thrive.

Medications and Other Causes

• Many medications list secretory diarrhea as a common side effect. Medications prescribed for asthma, depression and cardiac disease are among the most common of those that can cause secretory diarrhea as a side effect. Treatment of secretory diarrhea caused by medication is usually accompanied by a lowering of the dosage or a change to an alternative medication. Secretory diarrhea can also be caused by organic toxins like arsenic and mushroom toxins, ingesting of insecticides and overuse of caffeine.