As unpleasant as diarrhea is, this universal ailment rarely causes serious problems. Most people have diarrhea once or twice a year, according to the Cleveland Clinic.


Sometimes referred to as intestinal flu, diarrhea is usually caused by a virus in the bowel and generally lasts two or three days. But the condition – characterized by watery stool, abdominal cramps and an urgency for bowel movements – has many possible causes, which include:

  • Bacteria and parasites from contaminated food and water, which is common in developing countries and known as traveler’s diarrhea
  • Food intolerance, such as difficulty digesting dairy products, artificial sweeteners and fructose, a natural sugar found in honey and fruit
  • Medications such as antibiotics, which can disturb the natural balance of intestinal bacteria. Antacids and drugs for cancer and blood pressure can also cause diarrhea, according to the National Institutes of Health.
  • Surgery or radiation therapy
  • Digestive disorders such as celiac disease, ulcerative colitis, irritable bowel syndrome or Crohn’s disease, which tend to cause chronic diarrhea


The primary complication of diarrhea is dehydration caused by the loss of large amounts of water, salt and nutrients. According to the Mayo Clinic, dehydration can lead to other serious conditions such as low blood pressure, seizures, kidney failure or even death. Those with ongoing diarrhea should seek medical attention if they experience:

  • Dark urine or small amounts of urine
  • Rapid heart rate
  • Dry, flushed skin
  • Headaches or light-headedness
  • Fatigue
  • Irritability or confusion
  • Severe abdominal or rectal pain
  • Blood in the stool or black, tar-like stools

Diagnosis & Tests

Diagnosing diarrhea itself is simple, but doctors may want to determine the condition’s cause for those whose symptoms are severe and/or ongoing. According to the NIH, tests include:

  • Physical exam of the abdomen and questions about eating habits
  • Medication review, including over-the-counter drugs and supplements
  • Blood tests to rule out certain diseases
  • Stool culture to determine whether bacteria or parasites are present
  • Fasting tests, avoiding various foods to determine whether diarrhea responds to dietary changes
  • Sigmoidoscopy or colonoscopy, which allow doctors to view the colon and rectum internally
  • Imaging tests to rule out intestinal blockages or other abnormalities

Treatment & Medications

Most cases of diarrhea resolve spontaneously within a few days and all that is needed is preventing dehydration by replacing lost fluids, according to the NIH.

In the meantime, various over-the-counter medications may help firm the stool and decrease the urgency for bowel movements. These include loperamide hydrochloride (commonly known as the brand name Imodium AD), bismuth subsalicylate (brand name Pepto-Bismol) and attapulgite (brand name Kaopectate.

These medications, however are not recommended for diarrhea caused by bacterial infection or parasites, according to the NIH, since organisms will be trapped in the intestines if the diarrhea ceases before they are completely excreted.

The Cleveland Clinic recommends drinking two to three quarts or liters of liquids daily while recovering from diarrhea. While water is fine, it does not replace lost salt or nutrients, so better choices are broth, tea with honey, sports drinks and pulp-free juices. Avoid milk products, caffeine, alcohol, and apple and pear juices since they may worsen diarrhea.

Soft, bland foods are recommended as well, including bananas, plain rice, toast, crackers, boiled potatoes, smooth peanut butter, cottage cheese, noodles and applesauce. Because yogurt, cheese and miso contain probiotics, which contain strains of bacteria similar to those in a healthy intestine, they are also good choices. Avoid fatty, high-fiber or heavily seasoned foods for several days.