what causes diarrhea?

Diarrhea can be caused by a wide range of factors, which can be categorized into several main groups:

Infections

• Diarrhea is often a symptom of infections in the intestinal tract caused by bacterial, viral, and parasitic organisms. Common viral causes include norovirus, rotavirus, adenovirus, and astrovirus45.
• Bacterial pathogens such as Escherichia coli, Salmonella, Shigella, and Campylobacter can also cause diarrhea45.
• Parasitic infections like Cryptosporidium, Giardia, and Entamoeba spp. are additional causes4.

Food-Related Issues

• Food poisoning from contaminated food or water is a common cause of diarrhea. This can be due to microbes such as bacteria, viruses, or parasites235.
• Food allergies and intolerances, such as celiac disease, gluten allergy, lactose intolerance, fructose intolerance, and sucrose intolerance, can also lead to diarrhea235.

Medications

• Side effects from medications, including antibiotics, antacids containing magnesium, and certain cancer drugs, can cause diarrhea. Liquid medicines containing sugar alcohols like sorbitol, mannitol, and xylitol can also be a cause235.

Intestinal and Digestive Diseases

• Chronic conditions such as irritable bowel syndrome (IBS), Crohn’s disease, ulcerative colitis, and celiac disease can lead to persistent diarrhea235.
• Other digestive tract problems, including small intestinal bacterial overgrowth and pancreatic issues, can also cause chronic diarrhea5.

Surgical and Other Medical Procedures

• Surgery on the stomach, gallbladder, or intestines can result in chronic diarrhea or conditions like dumping syndrome35.

Functional Bowel Disorders

• Disorders of gut-brain interaction, such as functional diarrhea and IBS, can cause chronic diarrhea without an identifiable cause5.

Other Factors

• Travelers’ diarrhea can occur due to consuming contaminated food and water while traveling to areas with poor sanitation and hygiene5.
• Metabolic conditions like hyperthyroidism (overactive thyroid) can also cause diarrhea3.
• Laxative abuse and certain cancers can lead to diarrhea as well3.

Environmental and Hygiene Factors

• Poor hygiene and contaminated food or water, especially in areas with inadequate sanitation and access to clean water, significantly increase the risk of diarrhea4.