Diarrhea

What Is It?

Diarrhea is more frequent and more liquid bowel movements than normal. There are many causes, but diarrhea often is caused by an infection with bacteria, viruses or a parasite. Bacteria cause diarrhea either by invading the intestine or by producing a toxin that makes the intestine secrete more water. Food poisoning is caused by the ingestion of food contaminated with a parasite or bacterium, or the toxin produced by bacteria. Other causes of acute diarrhea include medication, inflammation of the lowest part of the intestine (ulcerative colitis) and stress, especially in people with irritable bowel syndrome. Some common medications that cause diarrhea are antibiotics, antacids with magnesium and laxatives. Antibiotic-associated diarrhea is a special situation, and requires consultation with a professional.

Symptoms

People with diarrhea usually have loose, watery stools. Less commonly, people pass frequent, small amounts of loose stool with mucous and blood. Other symptoms can include:

• Abdominal pain and cramping
• Vomiting
• Low-grade fever (under 101 degrees Fahrenheit)
• Chills
• Bloody stools
• Lack of bowel control

Frequent vomiting and diarrhea can lead to dehydration (abnormally low levels of body water) if too much fluid is lost from the body. Signs of dehydration include:

• Dry mouth
• Thirst
• Dry eyes
• Infrequent urination

Diagnosis

Since diarrhea has many possible causes, your doctor will ask you about your personal circumstances. Recent travel history or exposure to family members with similar symptoms might suggest an infection.

Your doctor will review your symptoms and exam you. If you have severe symptoms, your doctor also may ask for a stool sample. The specimen will be analyzed in a laboratory to look for infectious causes.

Expected Duration

Symptoms of diarrhea are usually most severe during the first 24 hours. Although some episodes of acute diarrhea last as long as 14 days, most go away within three to seven days.

Prevention

You can help to prevent diarrhea by practicing good hygiene. Most importantly, wash your hands frequently with soap and water, especially before eating, before preparing food, and after using the bathroom. Since some diarrhea is caused by food poisoning, avoid eating undercooked meats, raw seafood, or foods left out for several hours. If your episodes of diarrhea occur only rarely, a specific cause may not be found. If you experience recurrent episodes, try to identify the factors that trigger your symptoms, such as a reaction to medicine or certain foods, and avoid them.