Diarrhea

Diarrhea is loose, watery stools. A person with diarrhea typically passes stool more than three times a day. People with diarrhea may pass more than a quart of stool a day. Acute diarrhea is a common problem that usually lasts 1 or 2 days and goes away on its own without special treatment. Prolonged diarrhea persisting for more than 2 days may be a sign of a more serious problem and poses the risk of dehydration. Chronic diarrhea may be a feature of a chronic disease.

Diarrhea can cause dehydration, which means the body lacks enough fluid to function properly. Dehydration is particularly dangerous in children and older people, and it must be treated promptly to avoid serious health problems.

People of all ages can get diarrhea and the average adult has a bout of acute diarrhea about four times a year. In the United States, each child will have had seven to 15 episodes of diarrhea by age 5.

Symptoms

Diarrhea may be accompanied by cramping, abdominal pain, bloating, nausea, or an urgent need to use the bathroom. Depending on the cause, a person may have a fever or bloody stools.

Dehydration

Diarrhea can cause dehydration, which means the body has lost too much fluid and too many electrolytes and can’t function properly. Dehydration is particularly dangerous in children and in older adults and must be treated promptly to avoid serious health problems.

Signs of dehydration include

• thirst
• less frequent urination
• dry skin
• fatigue
• light-headedness
• dark-colored urine

Signs of dehydration in children include

• dry mouth and tongue
• no tears when crying
• no wet diapers for 3 hours or more
• sunken abdomen, eyes, or cheeks
• high fever
• listlessness or irritability
• skin that does not flatten when pinched and released

If you suspect that you or your child is dehydrated, call the doctor immediately. Severe dehydration may require hospitalization.

Preventing Dehydration

The fluid and electrolytes lost during diarrhea need to be replaced promptly because the body cannot function without them. Electrolytes are the salts and minerals that affect the amount of water in your body, muscle activity, and other important functions.

Although water is extremely important in preventing dehydration, it does not contain electrolytes. Broth and soups that contain sodium, and fruit juices, soft fruits, or vegetables that contain potassium, help restore electrolyte levels. Over-the-counter rehydration solutions such as Pedialyte, Ceralyte, and Infalyte are also good electrolyte sources and are especially recommended for use in children.

Causes

Acute diarrhea is usually related to a bacterial, viral, or parasitic infection. Chronic diarrhea is usually related to functional disorders such as irritable bowel syndrome or inflammatory bowel disease.

A few of the more common causes of diarrhea include the following:

• Bacterial infections. Several types of bacteria consumed through contaminated food or water can cause diarrhea. Common culprits include Campylobacter, Salmonella, Shigella, and Escherichia coli (E. coli).

• Viral infections. Many viruses cause diarrhea, including rotavirus, Norwalk virus, cytomegalovirus, herpes simplex virus, and viral hepatitis.

• Food intolerances. Some people are unable to digest food components such as artificial sweeteners and lactose—the sugar found in milk.

• Parasites. Parasites can enter the body through food or water and settle in the digestive system. Parasites that cause diarrhea include Giardia lamblia, Entamoeba histolytica, and Cryptosporidium.

• Reaction to medicines. Antibiotics, blood pressure medications, cancer drugs, and antacids containing magnesium can all cause diarrhea.

• Intestinal diseases. Inflammatory bowel disease, colitis, Crohn’s disease, and celiac disease often lead to diarrhea.

• Functional bowel disorders. Diarrhea can be a symptom of irritable bowel syndrome.

Some people develop diarrhea after stomach surgery or removal of the gallbladder. The reason may be a change in how quickly food moves through the digestive system after stomach surgery or an increase in bile in the colon after gallbladder surgery.

People who visit foreign countries are at risk for traveler’s diarrhea, which is caused by eating food or drinking water contaminated with bacteria, viruses, or parasites. Traveler’s diarrhea can be a problem for people visiting developing countries. Visitors to the United States, Canada, most European countries, Japan, Australia, and New Zealand do not face much risk for traveler’s diarrhea.

In many cases, the cause of diarrhea cannot be found. As long as diarrhea goes away on its own, an extensive search for the cause is not usually necessary.

How is the cause of diarrhea diagnosed?

Diagnostic tests to find the cause of diarrhea may include the following:

• Medical history and physical examination. The doctor will ask you about your eating habits and medication use and will examine you for signs of illness.

• Stool culture. A sample of stool is analyzed in a laboratory to check for bacteria, parasites, or other signs of disease and infection.

• Blood tests. Blood tests can be helpful in ruling out certain diseases.

• Fasting tests. To find out if a food intolerance or allergy is causing the diarrhea, the doctor may ask you to avoid lactose, carbohydrates, wheat, or other foods to see whether the diarrhea responds to a change in diet.

• Sigmoidoscopy. For this test, the doctor uses a special instrument to look at the inside of the rectum and lower part of the colon.

• Colonoscopy. This test is similar to a sigmoidoscopy, but it allows the doctor to view the entire colon.

• Imaging tests. These tests can rule out structural abnormalities as the cause of diarrhea.

Reference:

National Digestive Diseases Information Clearinghouse, USA.