What Is Diarrhea?
Most people think of diarrhea as an illness during which they have more frequent, loose, watery stools.
Almost everyone has it at some point. In developing countries, where illnesses that cause diarrhea are common and where health care is less available, diarrhea is a major health concern because of its potential to cause dehydration.
Diarrhea that comes on suddenly and goes away over a couple of weeks is called “acute diarrhea." Most people with this get better on their own.
Diarrhea that lasts more than 4 weeks is “chronic diarrhea." You usually need to go to a doctor so they can find the cause and treat you for any complications.
What Causes Diarrhea?
Many different things can cause diarrhea.
Infections: You may get an infection from contact with someone else. You may get one after having contaminated food or water. If you eat something that was improperly cooked or contaminated after cooking, the infection is called food poisoning. Diarrhea, cramps, and vomiting are common with food poisoning. Children who attend day care and their families are more likely to get these infections.
People who travel to foreign countries get “traveler’s diarrhea," usually after drinking bad water. Infectious diarrhea is a problem in developing countries, where it may be hard to keep waste water and sewage separate from water used to cook, drink, and bathe.
Medications: Many medicines can cause diarrhea. Some of the most common include:
- Antacids with magnesium
- Some antibiotics
- Chemotherapy drugs
- Cholesterol-lowering agents
- Thyroid hormone
Too much caffeine or alcohol: You may need to cut back on one or both to see if that does the trick.
Toxins such as insecticides, psychedelic mushrooms, and arsenic: They cause diarrhea, too.
A digestive problem: This could be lactose intolerance, celiac disease, or pancreatic problems.
Surgery to remove part of your small intestine: After that procedure, you may not be able to absorb everything you eat. Your doctor may call it short-bowel syndrome.
Removal of your gallbladder: The increase of bile in your colon from this procedure may result in watery stools.
Hormonal disorders: This includes overactive thyroid disease, diabetes, adrenal disease, and Zollinger-Ellison syndrome.
Certain rare tumors: Things like a carcinoid tumor and pheochromocytoma can bring diarrhea on.
Inflammatory bowel disease: Ulcerative colitis, Crohn’s disease, or microscopic colitis will give you diarrhea during flare-ups.
Irritable bowel syndrome (IBS): This may cause both diarrhea and constipation.
Ischemic bowel disease: This can be caused by blocked arteries. Symptoms might include abdominal pain with bloody diarrhea.
Radiation therapy for cancer: It can damage the intestine and cause diarrhea.
Other Medical Conditions
A number of noninfectious medical conditions may cause diarrhea. These include:
- Inability to digest certain foods, including lactose intolerance (difficulty digesting sugar found in dairy products); celiac disease (an immune reaction to consuming gluten, a protein found in wheat, barley, and rye); and pancreatic problems, such as those caused by cystic fibrosis, which interfere with production of important digestive substances.
- Surgery to remove part of your small intestine. A shortened small intestine may be unable to absorb all the substances you eat. This is referred to as short-bowel syndrome.
- Surgical removal of the gallbladder. An increase in bile in the colon may result in watery stools.
Certain diseases of the endocrine (hormonal) system, including overactive thyroid disease, diabetes, adrenal disease, and Zollinger-Ellison syndrome
Certain rare tumors (including carcinoid tumor and pheochromocytoma) that produce diarrhea-causing substances (hormones)
- Inflammation in the intestinal tract, which can result in chronic diarrhea. If you have inflammatory bowel disease (such as ulcerative colitis, Crohn’s disease, or microscopic colitis), you will have regular bouts of diarrhea during a flare-up of your disease.
- Irritable bowel syndrome, which may cause alternating bouts of diarrhea and constipation
Ischemic bowel disease, which can be caused by blocked arteries. Symptoms might include abdominal pain with bloody diarrhea.
Medications and Other Substances
Many medications can cause diarrhea. Some of the most common include antacids containing magnesium, laxatives, digitalis, diuretics, a number of antibiotics, chemotherapy drugs, cholesterol-lowering agents, lithium, theophylline, thyroid hormone, and colchicine.
Radiation therapy for prostate cancer or cancers in the abdomen can damage the intestine and cause diarrhea.
Toxins such as insecticides, psychedelic mushrooms, and arsenic can cause diarrhea, and overuse of caffeine or alcohol may contribute to diarrhea.