Diarrhea is the passage of loose or watery stools 3 or more times a day with or without discomfort. It happens when the water in the intestine is not being absorbed back into the body for some reason. Sometimes, diarrhea can be caused by an overflow of intestinal liquids around stool that is lodged in the intestine (impaction). Other causes can include chemotherapy; radiation therapy to the abdomen; medicines; infections; surgery; anxiety; supplemental feedings that contain large amounts of vitamins, minerals, sugar, and electrolytes; and tumor growth. Diarrhea caused by chemotherapy or radiation therapy may last for up to 3 weeks after treatment ends.

Alternative Names

Stools – watery; Frequent bowel movements; Loose bowel movements.

Types of Diarrhea:

1. Secretory Diarrhea

Either the gut is secreting more fluids than usual, or it cannot absorb fluids properly. In such cases structural damage is minimal. This is most commonly caused by a cholera toxin – a protein secreted by the bacterium Vibrio cholera.

2. Osmotic Diarrhea

Too much water is drawn into the bowels. This may be the result of celiac disease, pancreatic disease, or laxatives. Too much magnesium, vitamin C, undigested lactose, or undigested fructose can also trigger osmotic diarrhea.

3. Motility Related Diarrhea

Food moves too quickly through the intestines (hypermotility). If the food moves too quickly there is not enough time to absorb sufficient nutrients and water. Patients who had a vagotomy (removal or severing of the vagus nerve) as well as those with diabetic neuropathy are susceptible to this type of diarrhea.

4. Inflammatory Diarrhea

The lining of the gut becomes inflamed. This is usually caused by bacterial infections, viral infections, parasitic infections, or autoimmune problems such as IBS (inflammatory bowel disease). Tuberculosis, colon cancer and enteritis can also cause inflammatory diarrhea.

5. Dysentery

The presence of blood in the stools is usually a sign of dysentery, rather than diarrhea. Dysentery is caused by a release of excess water caused by an antidiuretic hormone from the posterior pituitary gland. Dysentery is one of the symptoms of Shigella, Entamoeba histolytica, and Salmonella.

Causes of Diarrhea:

The most common cause of diarrhea is a virus that infects the bowel. The infection usually lasts for two days and is sometimes called “intestinal flu.” Diarrhea also may be caused by:

• Infection by bacteria (the cause of most types of food poisoning)
• Infections by other organisms
• Eating foods that upset the digestive system
• Allergies to certain foods
• Medications
• Radiation therapy

Diarrhea also may follow constipation, especially for people who have irritable bowel syndrome.

Signs and Symptoms:

Diarrhea is a symptom of another health issue, such as an infection or a virus. Chronic diarrhea — lasting longer than 4 weeks — can be a sign of a serious illness, such as inflammatory bowel disease.

Symptoms may include:

• Frequent and loose stools
• Abdominal pain, cramping
• Fever, chills, general sick feeling
• Thirst
• Weight loss

If your child has diarrhea, call your pediatrician if it lasts more than 24 hours or if your child seems dehydrated. For an infant, that could mean having a dry diaper for several hours or crying without tears.