What Is Diarrhea?
Most people think of diarrhea as an illness when 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 might be less easily accessible, 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 get better on their own.
If diarrhea lasts more than four weeks, it's considered "chronic diarrhea." You usually need to go to a doctor so they can find the cause of chronic diarrhea and treat you for any complications.
What Causes Diarrhea?
Different things can cause diarrhea, ranging from infections to treatments for certain types of illnesses. Acute diarrhea is diarrhea that usually lasts about a week or so and, in many cases, goes away without any treatment.
Acute diarrhea is most often caused by viral, bacterial, or parasitic infections. You can get an infection from contact with someone else who has it or by consuming contaminated food or water. If you eat something that was improperly cooked or contaminated after cooking, the infection is often called food poisoning. Diarrhea, cramps, and vomiting are common with food poisoning. Children, especially if they're in daycare, often get sick with infections like gastroenteritis (often called "stomach flu") by putting their hands in their mouth after they've touched something that had the virus on it. They then can pass it to their families.
People who travel to some foreign countries can get "traveler's diarrhea," usually after drinking contaminated water or drinking something with ice cubes that were made from contaminated 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.
Can stress cause diarrhea?
Many people feel their gut tighten up and they get cramps when they're anxious or stressed. This can lead to diarrhea. Some may think it's "in their head," but stress does cause diarrhea in some people (or it can cause constipation in others).
Types of Diarrheas and Their Causes
Chronic diarrhea causes
If you have to go to the bathroom three or more times a day for at least four weeks, this is chronic diarrhea.
Certain illnesses and sometimes the treatment for others can cause chronic diarrhea. Some of the more common reasons include:
- Lactose intolerance, the inability to digest lactose in dairy products
- Intestinal diseases:
- Celiac disease
- Irritable bowel syndrome (IBS)
- Inflammatory bowel disease (IBD; ulcerative colitis and Crohn's disease)
- Other disorders:
- Diabetes
- Hyperthyroid (overactive thyroid)
- Adrenal gland disorders
- Pancreatitis and other disorders that affect the pancreas
- Zollinger-Ellison syndrome
- Rare tumors:
- Carcinoid tumors
- Pheochromocytoma
- Ischemic bowel disease, caused by blocked arteries to the bowels
Some medical and surgical treatments that can also cause chronic diarrhea:
- Surgery to remove part of your small intestine might cause short-bowel syndrome, which means you can't absorb certain types of foods. Examples of why someone might need this type of surgery include having tumors or other growths removed, treatment for IBD, or having an obstruction removed.
- Gallbladder removal can cause diarrhea for a while after surgery, but it stops shortly after for most people.
- Bariatric surgery (like gastric bypass) can cause diarrhea if you don't follow the food recommendations.
- Radiation therapy for cancer if the treatment is aimed toward the abdomen or pelvis because the radiation can cause inflammation in the bowels.
Watery diarrhea causes
Watery diarrhea, stool that seems to be more water than anything else, can be caused by a number of things, including:
- Adrenal gland disorders
- Diabetes-related neuropathy, damage to the nerves in the intestines caused by high blood sugar levels
- Having too much bile in your gut, called bile acid diarrhea/malabsorption
- Hyperthyroidism
- IBS
- Microscopic colitis
- Vagotomy, a procedure that cuts part of the vagus nerve that goes to your stomach
Bloody diarrhea causes
If you see blood in your diarrhea, this can be a serious issue and should be treated like a medical emergency. There are many possible causes, including:
- Infections
- IBD
- Diverticulitis
- Cancer
Yellow diarrhea causes
Although stool is usually brown, it may be yellowish sometimes. If you have yellow diarrhea, it could be caused by:
- Steatorrhea, or excess fat in your stool; this can be caused by problems affecting your pancreas, liver, or bile duct
- Crohn's disease
- Celiac disease
- Whipple's disease
- Small intestinal bacterial overgrowth
- Giardiasis
- Short gut syndrome
- Lymphoma
- Amyloidosis
You could also have yellowish stool from eating a lot of food that is yellow or orange, like sweet potatoes, carrots, or foods with yellow food coloring.
Medications and Substances That Cause Diarrhea
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.
Can alcohol cause diarrhea?
Drinking too much alcohol, especially beer and wine, can cause diarrhea the next day. The alcohol stays in your digestive tract for quite a while as your body absorbs it. While it's there, the alcohol can cause damage to the cells so your body responds by trying to push the alcohol out.
Can caffeine cause diarrhea?
Caffeine can act like a laxative, especially if you drink more than 2 or 3 cups per day. The chemicals in caffeine stimulate your bowels to move. Switching to decaffeinated might help but not always because it also has a laxative effect.
If you get your caffeine through coffee, what you add to your coffee may add to the risk of having diarrhea. For example, if you're lactose intolerant, the cream or milk will make you go to the bathroom, as can some types of sweeteners, like sorbitol and mannitol.
Takeaways
It's not unusual to have diarrhea from time to time. You might get an infection or eat something that makes you sick. But sometimes diarrhea is caused by something serious, like a bowel disease, or from medical treatment, like bowel surgery. If you have diarrhea that is frequent and lasts more than a few days, contact your doctor as soon as possible to see what might be causing it.
Diarrhea Causes FAQs
What causes explosive diarrhea after eating?
Explosive diarrhea can be caused by dumping syndrome or rapid gastric emptying, something that happens if the food in your stomach enters your small bowel too quickly. This can happen to people who have had surgery on their stomach or intestines. Explosive diarrhea also can happen to people who have diabetes and some other disorders, as well as those who have lactose intolerance.
What is the main cause of diarrhea?
The most common cause of diarrhea is a viral infection.
Why do I have extremely watery diarrhea?
There are many possible reasons to have watery diarrhea, such as infections to lactose intolerance or diseases that affect your liver, pancreas, and intestines. If you have watery diarrhea and it doesn't go away, speak to your doctor so you can try to find the cause.
What viruses cause diarrhea?
The most common virus that causes diarrhea is norovirus.
