Causes

Causes

Causes of diarrhea include;
• Radiation therapy
• Running (Some people get “runner’s diarrhea” for reasons that aren’t clear)
• Some cancers
• Surgery on your digestive system
• Trouble absorbing certain nutrients, also called “malabsorption”
• Alcohol abuse
• Allergies to certain foods
• Diabetes
• Diseases of the intestines (such as Crohn's disease or ulcerative colitis)
• Eating foods that upset the digestive system
• Infection by bacteria (the cause of most types of food poisoning) or other organisms
• Laxative abuse
• Medications
• Overactive thyroid (hyperthyroidism)

Inflammatory bowel disease (IBD) is another cause of chronic diarrhea. It is a term used to describe either ulcerative colitis or Crohn's disease. There is often blood in the stool in both conditions.
Other major causes of chronic diarrhea include:

• Microscopic colitis - usually affects older adults. The persistent diarrhea is often during the night.
• Malabsorptive and maldigestive diarrhea - the first is caused by impaired nutrient absorption, the second by impaired digestive function. Celiac disease is one example.
• Chronic infections - a history of travel or antibiotic use can be clues to chronic diarrhea; various bacteria and parasites can be the cause.
• Drug-induced diarrhea - the obvious cause is laxatives, but a list of other drugs can also lead to diarrhea including antibiotics.
• Endocrine causes - sometimes hormones are the cause, for example, in conditions including Addison disease and carcinoid tumors.
• Cancer causes - neoplastic diarrhea is associated with a number of gut cancers.