What Causes Chronic Diarrhea?
There are many causes of chronic diarrhea; these may be different for children and adults. Causes can be grouped into two categories: diarrhea caused by an infection and diarrhea not caused by an infection. Sometimes, the cause of chronic diarrhea remains unknown.
Diarrhea caused by an infection may result from the following:
- Parasites, such as Cryptosporidium parvum, Cyclospora cayetanensis, Entamoeba histolytica, Giardia lamblia, or Microsporidia
- Bacteria, such as Campylobacter, Clostridium difficile, Escherichia coli, Listeria monocytogenes, Salmonella enteritidis, or Shigella
- Viral infections, such as rotavirus, HIV, or Norwalk agent
Diarrhea not caused by an infection may result from the following:
- High blood pressure medications
- Cancer drugs
- Crohn's disease
- Diabetes, thyroid, and other endocrine diseases
- Food additives (sorbitol, fructose, and others)
- Food allergies
- Previous surgery or radiation of the abdomen or gastrointestinal tract
- Reduced blood flow to the intestine
- Heredity—certain diseases occur more often in related family members.