What Are the Causes of Diarrhea?

Diarrhea refers to loose stools, and its causes are numerous. It is necessary to determine the cause based on acute or chronic diarrhea. Acute diarrhea includes enteritis, poisoning, medication, and other diseases; chronic diarrhea includes intestinal tuberculosis, Crohn's disease, colorectal cancer, irritable bowel syndrome, etc. If there are multiple occurrences of diarrhea or accompanied by other symptoms, it is necessary to seek medical attention promptly to avoid delayed treatment.

(1) Enteritis: This can be caused by viruses (such as rotavirus, Norwalk virus, Coxsackie virus, and Echo virus), bacteria (such as Escherichia coli, Salmonella, Shigella, Vibrio cholerae), or parasites (such as Entamoeba histolytica and Giardia lamblia).

(2) Poisoning: This can include food poisoning from uncooked lentils, poisonous mushrooms, puffer fish, heavy metal poisoning, pesticide poisoning, etc.

(3) Medication: Laxatives, cholinergic drugs, digitalis drugs, etc.

(4) Other Diseases: Acute exacerbation of ulcerative colitis, acute necrotic enteritis, food allergies, etc.

The causes of chronic diarrhea are more complex than acute diarrhea. They can include intestinal mucosal lesions, excessive bacterial proliferation in the small intestine, defects in intestinal transport function, insufficient digestive capacity, intestinal motility disorders, as well as certain endocrine diseases and extra-intestinal tumors.

Diseases that can cause chronic diarrhea include:

(1) Infectious intestinal diseases: chronic amebic dysentery, chronic bacterial diseases, intestinal tuberculosis, giardiasis, schistosomiasis, and intestinal candidiasis.

(2) Non-infectious inflammatory intestinal diseases: inflammatory bowel disease (Crohn's disease and ulcerative colitis), radiation enteritis, ischemic colitis, diverticulitis, and uremic enteritis.

(3) Tumors: colorectal cancer, colonic adenomas (polyps), small intestine malignant lymphomas, amine precursor uptake and decarboxylation cell tumors, gastrinomas, carcinoid tumors, and vasoactive intestinal polypeptide tumors.

(4) Malabsorption in the small intestine: primary malabsorption in the small intestine and secondary malabsorption in the small intestine.

(5) Intestinal motility disorders such as irritable bowel syndrome.