Diarrhea

Diarrhea is a medical condition characterized by the passage of loose or liquid stools with increased frequency, typically more than three times a day, and sometimes in larger volumes than usual. Diarrhea can be caused by poor nutrition, bacterial, viral, or parasitic infections, gastrointestinal inflammation, non-gastroenterological diseases, use of various medications, or psychological stress.

Pathophysiologically, diarrhea results from one or more of the following mechanisms: impaired absorption of water and electrolytes in the intestine, increased secretion of fluids into the intestinal lumen, accelerated intestinal motility, or damage to the intestinal mucosa.

Clinically, diarrhea is classified by duration:

• Acute Diarrhea: Lasts up to 14 days, usually due to infection.
• Persistent Diarrhea: Lasts between 14 and 30 days.
• Chronic Diarrhea: Lasts over 4 weeks, and is often related to inflammatory bowel diseases, functional disorders, or malabsorption issues.

Diarrhea may be accompanied by additional symptoms such as abdominal pain, bloating and gas, fever, blood or mucus in the stool, unexplained weight loss, and signs of dehydration. The clinical significance and the need for medical investigation depend on the duration of the symptom, its severity, the patient's age, and the presence of warning signs.