Bacterial infections, food intolerance, medications, intestinal disease and bowel disorders are the five most common causes of diarrhea in the elderly, according to HealthinAging.org. A person has diarrhea when she passes at least three liquid stools each day.
Antibiotic regimens are a common reason why an elderly person has diarrhea. Along with other medications such as pain relievers, antibiotics create havoc with the bacterial balance in the intestines, states HealthinAging.org.
The inability to digest certain types of food, such as lactose in dairy products or gluten in wheat-containing foods, can also cause diarrhea, reports HealthinAging.org. The best treatment for food intolerance is to stop eating the foods that trigger diarrhea.
Along with a dire need to use the bathroom, symptoms of diarrhea may include fever, pain, cramping, nausea and bloating, reports HealthinAging.org. Diarrhea falls under the classification of either acute or chronic. Acute diarrhea usually abates within 21 days. Common causes of acute diarrhea include parasites or infection.
Chronic diarrhea continues past three weeks and requires a visit to the doctor. Commonly caused by a disease such as irritable bowel syndrome or inflammatory bowel disease, chronic diarrhea can lead to dehydration and even death, particularly in the elderly, states HealthinAging.org. People with diarrhea should drink plenty of liquids to make up for lost fluids.