Bacterial, viral and parasitic infections cause most cases of acute diarrhea, which lasts up to two days, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Medical disorders, such as irritable bowel syndrome, may cause chronic diarrhea, which lasts at least four weeks.
Medications, such as antibiotics and laxatives containing magnesium, may also cause diarrhea in some people, according to MedlinePlus. To determine the exact cause of diarrhea, a physician may order stool cultures, blood tests or other diagnostic tests, according to the NIDDK.
Loose and watery stools are the most common symptoms of diarrhea. Other symptoms include bloating, fever and abdominal cramps. If an individual experiences black or bloody stools, severe abdominal pain or a fever above 101 degrees Fahrenheit (100.4 degrees Fahrenheit in children), she should visit a healthcare provider as soon as possible, according to Mayo Clinic.
In most cases, diarrhea symptoms resolve on their own, according to Mayo Clinic. To lessen symptoms, individuals with diarrhea should drink plenty of fluids, avoiding caffeinated and alcoholic beverages. They should also avoid foods high in fiber, fat and dairy until symptoms subside. Over-the-counter anti-diarrheal medications containing loperamide and bismuth subsalicylate may reduce the frequency of loose bowel movements. Individuals with bloody diarrhea, however, should avoid taking over-the-counter anti-diarrheals, as these medications sometimes interfere with healing, according to the NIDDK. Antibiotics may be prescribed to treat the underlying problem.