- Diarrhea typically occurs as the result of a bacterial or viral infection. Another common cause is food poisoning or food intolerance.
- Chronic diarrhea occurs in people with diseases in their large intestine such as Crohn’s disease or colitis.
- Most of the time diarrhea clears up on its own, but depending on what’s causing the condition, it can be treated with medication.
After a particularly fatty feast or bout of the flu, diarrhea often rears its gassy, bloated, and uncomfortable presence. A spell of it often consists of loose, watery bowel movements that come on suddenly. People experiencing diarrhea are often hesitant to be far from a bathroom.
Typically, diarrhea occurs due to a virus, such as the stomach flu, in the digestive system. It lasts no more than a few days. However, long-term or frequent affliction can indicate other chronic diseases within the large intestine (or colon).
Here are the 12 most common causes of diarrhea…
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Bacterial or Viral Infection
Infections from either bacteria, viruses, or parasites typically cause sudden diarrhea (clinically known as acute diarrhea). The Mayo Clinic lists Norwalk virus, cytomegalovirus, rotavirus, and viral hepatitis as some of the most common viral infections causing diarrhea. Another common one is the norovirus. Health.com notes that there have been several outbreaks of this virus in close quarters, including cruise ships, nursing homes, schools, and prisons, because it spreads so quickly from person to person. Thankfully, stomach bugs from viral infections tend to work their way out of the body within a few days.
Similar to viral infections, there are many bacterial infections that can enter the body through contaminated water or food (digestive tract infections that are spread through food or water are called food-borne illnesses). The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) lists Campylobacter, Escherichia coli, Salmonella, and Shigella as the most common for causing diarrhea.
Bacterial infections will not go away quickly on their own without treatment. NIDDK also notes that some people may have trouble digesting certain foods such as carbohydrates, lactose or proteins, after suffering from an infection.