Is diarrhea dangerous?

For the guy cleaning the latrine, it sure is. And sometimes it can be for infants and older people; diarrhea (and the water and salt loss that goes with it) claims more infants worldwide than any other problem.

But for most Americans or developed-world adults, the question isn't about danger; it's about hydration and whether we can keep enough water in when we get diarrhea. The large bowel's job is to re-absorb water, so during diarrhea these mechanisms are paralyzed.

If you are having more than four episodes a day (or enough to disrupt your life) for more than three days, you probably should see a doctor. Bacteria and viruses will run their course, but taking chicken soup with rice helps by bringing sugar and salt to the bowel wall where they can be absorbed at least a little.

If the diarrhea lasts longer, you need to worry about parasites (like Giardia) or allergies from the very rich network of immune cells in the bowel wall.

Foods like milk or wheat or barley or oats or rye can irritate the intestines and you will only diagnose this by avoiding these foods for a week and seeing if you feel better.

YOU: The Owner's Manual, Updated and Expanded Edition: An Insider's Guide to the Body that Will Make You Healthier and Younger

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YOU: The Owner's Manual, Updated and Expanded Edition: An Insider's Guide to the Body that Will Make You Healthier and Younger

Between your full-length mirror and high-school biology class, you probably think you know a lot about the human body. While it's true that we live in an age when we're as obsessed with our bodies as...
Diana Meeks
Diana Meeks on behalf of Sigma Nursing
Family Practitioner

The biggest danger from diarrhea is dehydration. With diarrhea there is an increased loss of water and electrolytes in the liquid stool. Dehydration can result when these losses are not replaced and a deficit of water and electrolytes develops. An adult normally loses approximately 5ml/kg  of fluid through stool in a day. However with diarrhea the amount of fluid lost goes up to 200ml/kg or more per day.

The human body needs water to maintain enough blood and fluids to function properly. Along with fluids the body also needs electrolytes or the salts that are normally found in the blood, fluids and cells. Moderate dehydration may cause organ dysfunction and severe dehydration can cause death. Persons at most risk for dehydration from diarrhea are babies and young children, pregnant women, persons with chronic diseases and the elderly.

Diarrhea that does not resolve in a couple of days may be a sign of a more serious problem. Prolonged diarrhea or the presence of  a strong pain in the abdomen or rectum, a fever, or blood in the stools, are some reasons to seek care from a health care provider.

Deborah Davis, DNP
OBGYN (Obstetrician & Gynecologist)
Acute diarrhea diseases are among the leading causes of mortality in infants and young children in many developing countries.  In most cases, death is caused by dehydration.  Dehydration from diarrhea can be prevented by giving extra fluids at home, or it can be treated simply, effectively, and cheaply in all age-groups and in all but the most severe cases by giving patients by mouth an adequate glucose-electrolyte solution.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.