Diarrhea

Definition

Diarrhea is loose, watery, and frequent stool. Diarrhea is considered chronic (long-term) when you have had loose or frequent stools for more than 4 weeks.

Alternative Names

Considerations

Diarrhea in adults is usually mild and goes away quickly without complications. In infants and children (especially under age 3), diarrhea can cause dehydration fairly quickly.

Causes

The most common cause of diarrhea is viral gastroenteritis, a mild viral infection that goes away on its own within a few days. This condition is often called the stomach flu. Viral gastroenteritis often occurs in mini-epidemics in schools, neighborhoods, or families.

Food poisoning and traveler's diarrhea are two other common causes of diarrhea. They occur as a result of eating food or drinking water contaminated with bacteria or parasites.

Medications, especially antibiotics, laxatives containing magnesium, and chemotherapy for cancer treatment, can also cause diarrhea.

• Malabsorption syndromes such as lactose intolerance
• Inflammatory bowel diseases (Crohn's disease and ulcerative colitis)
• Irritable bowel syndrome (IBS)
• Celiac disease

Other less common causes of diarrhea include:

• Zollinger-Ellison syndrome
• Nerve disorders like autonomic neuropathy or diabetic neuropathy
• Carcinoid syndrome
• Gastrectomy (partial removal of the stomach)
• High dose radiation therapy

References

Yates J. Traveler's diarrhea. Am Fam Physician. 2005; 71(11): 2095-2100.

Guerrant RL. Practice guidelines for the management of infectious diarrhea. Clin Infect Dis. 2001; 32(3): 331-351.