Reviewed on 7/22/2022

What Is Diarrhea?

Early Sign of Diarrhea
An episode of loose stools is an early sign of diarrhea.

Facts and Definition of Diarrhea

  • Diarrhea is the frequent passage of loose, watery, soft stools with or without abdominal bloating, pressure, and cramps commonly referred to as gas or flatulence.
  • Seek medical care if severe abdominal pain, fever, dehydration, rectal bleeding, sleepiness, or vomiting accompany diarrhea. People who have diarrhea and are pregnant or have underlying medical conditions should also see a doctor.
  • Treatment of diarrhea depends upon the cause of the loose stools, as well as the patient's general health.

Causes of diarrhea include viral and bacterial infections, as well as parasites, intestinal disorders or diseases (such as irritable bowel syndrome [IBS]), reactions to medications, and food intolerance. The main symptom of diarrhea is watery, liquid stools. In addition, other symptoms of diarrhea include the following:

  • Stomach cramps
  • Fever
  • Bloating
  • Bowel movement urgency
  • Dehydration

Diarrhea is usually diagnosed by the appearance of the symptoms, and no tests may need to be ordered. In some cases, a doctor may order a stool culture, blood tests, a colonoscopy, or imaging tests such as X-rays or CT scans to determine an underlying cause.

In most cases, diarrhea can be treated at home and it will resolve itself in a few days. Drink plenty of fluids, and follow the "BRAT" diet (bananas, rice, applesauce, and toast) to help ease symptoms. Take care to ensure infants and children stay hydrated. Electrolyte solutions such as Pedialyte can be helpful.

Over-the-counter (OTC) antidiarrheal medications may provide some relief of symptoms, including loperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol, Kaopectate, etc.). Consult your doctor before treating diarrhea with these drugs, as some people may need to avoid them. Do not give them to children under 5 years of age. The prognosis for diarrhea is generally good and in most cases, symptoms will resolve in a few days.

Diarrhea is the frequent passage of loose, watery, soft stools with or without abdominal bloating, pressure, and cramps commonly referred to as gas. It can come on suddenly, run its course, and be helped with home care to prevent complications such as dehydration.

  • Diarrhea is one of the most common illnesses in all age groups and ranks along with the common cold as the main cause of lost days of work or school. People of all ages can suffer from the condition, and the average adult has one episode of acute diarrhea per year, and young children average 2 acute episodes per year.
  • Diarrhea and related complications can cause severe illness. The most significant cause of severe illness is the loss of water and electrolytes. In diarrhea, fluid passes out of the body before it can be absorbed by the intestines. When the ability to drink fluids fast enough to compensate for the water loss because of diarrhea is impaired, dehydration can result. Most deaths from diarrhea occur in the very young and the elderly whose health may be put at risk from a moderate amount of dehydration.
  • Diarrhea can be further defined in the following ways:
    • Chronic diarrhea is the presence of loose or liquid stools for over 2 weeks
    • Acute enteritis is inflammation of the intestine
    • Viral gastroenteritis (stomach flu) is a type of infectious diarrhea associated with nausea and vomiting
    • Dysentery is a type of diarrhea that contains blood, pus, or mucus

15 Causes of Diarrhea

Causes of Diarrhea
Adenovirus is one common cause of diarrhea.

Viral infections cause most cases of diarrhea and are typically associated with mild-to-moderate symptoms with frequent, watery bowel movements, abdominal cramps, and a low-grade fever. Viral diarrhea generally lasts approximately three to seven days.

The following are the common causes of diarrhea caused by viral infections (viral gastroenteritis):

  • Rotavirus is a common cause of diarrhea in infants.
  • Norovirus (for example, Norwalk virus, caliciviruses) is the most common cause of epidemics of diarrhea among adults and school-age children (for example, cruise ship infection, schools, nursing homes, day care facilities, and restaurants).
  • Adenovirus infections are common in all age groups.
Causes of Diarrhea
Bacterial diarrhea can also come with vomiting and cramps.

Bacterial infections cause the more serious cases of infectious diarrhea. Typically, infection with bacteria occurs after eating contaminated food or drinks (food poisoning). Bacterial infections also cause severe symptoms, often with vomiting, fever, and severe abdominal cramps or abdominal pain. Bowel movements occur frequently and may be watery and individuals may experience "explosive diarrhea" which is a very forceful, almost violent, expulsion of loose, watery stool along with gas.

The following are examples of diarrhea caused by bacterial infections:

  • In more serious cases, the stool may contain mucus, pus, or blood. Most of these infections are associated with local outbreaks of disease. Family members or others eating the same food may have similar illnesses.
  • Foreign travel is a common way for a person to contract traveler's diarrhea. (Traveler's diarrhea also may be caused by unfamiliar viruses or parasites.)
  • Campylobacter, salmonellae, and Shigella organisms are the most common causes of bacterial diarrhea.
  • Less common causes are Escherichia coli (commonly called E. coli) Yersinia, and Listeria.
  • Medications that one takes long-term may cause chronic diarrhea, including antibiotic-associated diarrhea. Use of antibiotics can lead to an overgrowth of Clostridium difficile (C diff) bacteria in the intestines.

Parasites cause infection of the digestive system by the use of contaminated water. Common parasitic causes of diarrheal disease include Giardia lamblia, Entamoeba histolytica, and Cryptosporidium.

Intestinal disorders or diseases (including those that affect the small intestine or colon) including inflammatory bowel disease including ulcerative colitis and Crohn's disease, irritable bowel syndrome (IBS), diverticulitis, microscopic colitis, and celiac disease, and malabsorption (trouble digesting certain nutrients) are non-infectious causes of chronic diarrhea. Many of these disorders can cause the diarrhea to be yellow in color.

Causes of Diarrhea
Antacids, weight loss drugs, and cancer drugs can cause diarrhea.

Reaction to certain medications can cause drug-induced diarrhea including antibiotics, blood pressure medications, cancer drugs, gout medications, weight loss drugs, and antacids (especially those containing magnesium).

Intolerance or allergies to foods such as artificial sweeteners found in sugar-free foods and lactose intolerance (to the sugar found in milk) can cause chronic diarrhea.

Alcohol abuse can cause diarrhea. Both binge drinking and chronic alcoholism may lead to loose stools.

Laxative abuse is one of the biggest self-induced causes of diarrhea, by taking too many laxatives, or taking them too frequently.

Diabetic diarrhea can be a complication of diabetes.

How to Treat Diarrhea
Diarrhea may last up to three weks after chemotherapy ends.

Radiation therapy or chemotherapy may cause loose stools and the diarrhea may last for up to three weeks after treatment ends.

Some cancers are more likely to cause diarrhea, including carcinoid syndrome, colon cancer, lymphoma, medullary carcinoma of the thyroid, pancreatic cancer, and pheochromocytoma.

Digestive surgery including stomach or intestinal surgery may cause diarrhea.

Running can cause diarrhea (sometimes referred to as "runner's trots"). This usually happens after longer distances over 10K or particularly hard runs.

7 Common Symptoms and Signs of Diarrhea

  1. Watery, liquid stools: The stools may be any color. The passage of red stools suggests intestinal bleeding and could be a sign of a more severe infection. The passage of thick, tarry black stools suggests significant bleeding in the stomach or upper portions of the intestine and is not usually caused by acute infections. Diarrhea may appear green in color because stool passes through the intestines faster than usual.
  2. Abdominal cramps: Occasionally diarrhea is accompanied by mild-to-moderate abdominal pain. Severe abdominal or stomach pain is not common and, if present, may suggest a more severe disease.
  3. Fever: A high fever is not common. If present, the affected person may have a more severe illness than acute diarrhea.
  4. Bloating and gas
  5. Urgent feeling or need to have a bowel movement
  6. Dehydration: If diarrhea leads to dehydration, it is a sign of a potentially serious disease. Signs and symptoms of dehydration include the following:
    1. Adults may be very thirsty and experience dry mouth.
    2. The skin of older people may appear to be loose. The elderly may also become very sleepy or have behavioral changes and confusion when dehydrated.
    3. Dehydrated infants and children may have sunken eyes, dry mouths, and urinate less frequently than usual. They may appear very sleepy or may refuse to eat or drink.
  7. Infection: Certain infections may cause diarrhea that may also be accompanied by bloody stools, fever and chills, lightheadedness and dizziness, and vomiting.

When Should You Seek Medical Care for Diarrhea?

Diarrhea can usually be treated with home care. In some cases, it may become more severe. A person should go to a hospital emergency department in the following situations:

  • If the person has the condition along with high fever, moderate-to-severe abdominal pain, or dehydration that cannot be managed by drinking fluids
  • If diarrhea appears to contain blood (it may be bright red or may look like black, thick tar)
  • If the person is sleepy and is not acting like their usual selves (others may notice this and take the person to the emergency department)

Call a doctor if a person has any of these complications:

  • Vomiting and inability to tolerate any food or to keep liquids down
  • Signs of dehydration
  • High fever, significant abdominal pain, frequent loose bowel movements, or bloody diarrhea
  • If he or she is elderly or has serious underlying medical problems, particularly diabetes, heart, kidney, or liver disease, or HIV/AIDS (contact a doctor when diarrhea first begins as the person may be at higher risk for developing complications)
  • A parent or caregiver needs advice about preventing dehydration in newborns and infants
  • Symptoms do not improve in two to three days or appear to become worse
  • If he or she develops diarrhea after travel within their home country or foreign travel; or if a woman is pregnant

For cases of chronic diarrhea, your primary care provider may consult with a gastroenterologist (a specialist in disease of the digestive tract).

What Procedures and Tests Diagnose Diarrhea?

In healthy people with diarrhea, and who appear well otherwise, the doctor may elect to do no tests at all. Stool cultures (when a sample of the stool is taken and examined in the lab for certain bacteria or parasites) are not usually necessary unless there is a high fever, blood in the stool, recent travel, or prolonged disease.

  • Stool sample: In some cases, the healthcare professional may send a sample of the stool (or sometimes a cotton swab from the patient's rectum) to the laboratory to evaluate if the cause of diarrhea can be determined (such as certain bacteria or parasites present in the body). It usually takes approximately 1-2 days for the results of these tests.
  • Blood test: Blood tests are sometimes necessary for patients with other medical problems or with severe disease.
  • Colonoscopy: A colonoscopy is an endoscope procedure that allows the physician to view the entire colon to evaluate for infections or structural abnormalities that could cause the condition.
  • Imaging tests: Imaging tests such as X-rays or CT scans are performed to rule out structural abnormalities as the cause of diarrhea, particularly when pain is a prominent symptom.

List of Natural and Home Remedies for Adults and Children for Diarrhea

Treatments for Adults

  • Adults should drink plenty of fluids to avoid dehydration.
  • Replenishing water loss (due to diarrhea) is important. Avoid milk as it can make diarrhea worse. Sports beverages (for example, Gatorade or Powerade) can be beneficial because they replenish electrolytes in addition to providing hydration.
  • If the patient is able to eat, avoid greasy or fatty foods. Adults, infants, toddlers, and children should be encouraged to follow the "BRAT" diet (bananas, rice, applesauce, and toast). The BRAT diet (diarrhea diet) is a combination of foods to eat to treat diarrhea. If diarrhea is accompanied by nausea, have the person suck on ice chips until the nausea stops. After the diarrhea subsides, avoid alcoholic beverages and spicy foods for two additional days.
  • Individuals may be able to continue their usual activities if they are mildly ill with diarrhea; however, strenuous exercise should be avoided because exercise increases the risk of dehydration.
  • If you are pregnant women and have diarrhea make sure to rehydrate to avoid dehydration, and consult your doctor.

Treatments for Toddlers and Children

Dehydration in children and toddlers can be a great concern. Loose stools are more common in breastfed newborns than in formula-fed babies, so check with your doctor about to expect for your child.

  • Infants and toddlers pose special problems because of their increased risk of dehydration. They should be offered a bottle frequently. Solutions such as Pedialyte may be more appealing than water. These fluids also contain necessary electrolytes lost with diarrhea. Never use salt tablets as they may worsen diarrhea.
  • Children with frequent stools, fever, or vomiting should stay at home and avoid school and day-care until these symptoms go away. This allows the child to rest and recover and prevents other children from being exposed to possible infection.
  • As mentioned previously, infants, toddlers, and children should be encouraged to follow the BRAT diet (bananas, rice, applesauce, and toast). The BRAT diet (diarrhea diet) is a combination of foods used for decades to treat diarrhea.

Are herbs safe to take for diarrhea?

  • Certain plant leaves contain tannins that are considered to be diarrhea remedies. Notably blackberry, blueberry, and raspberry leaves when taken as tea may help diarrhea.
  • Do not eat fresh blueberries because they may make the diarrhea worse.
  • If you're pregnant avoid high doses of tannins.
  • Chamomile tea may also act as a diarrhea remedy.

NOTE: If using remedies involving homeopathy, herbs, dietary and nutritional supplements, acupressure, aromatherapy, and other alternative or complementary methods, these products and techniques have not been scientifically proven to treat, prevent, or cure any disease. Side effects and serious interactions with prescription and nonprescription medications (OTC) are always a possibility. Tell your doctor about every prescription medication, OTC medication, vitamin, and supplement an individual uses, and seek medical advice for any health concerns prior to taking any medication or remedy. Keep a log of all medications and supplements (prescription or OTC), vitamins, supplements, and herbs in your wallet or purse in case of emergency.

List of Over-the-Counter (OTC) Medications

The use of anti-motility medications, although controversial, may help get rid of diarrhea. These drugs slow down the intestinal movement and stop diarrhea symptoms. These medications include loperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol, Kaopectate, etc).

  • Such medications are not recommended for infants and children younger than 5 years of age.
  • In otherwise healthy adults who are not severely ill with diarrhea, loperamide is probably safe and is effective in decreasing the number of stools per day and the total duration of the diarrhea.
  • Bismuth subsalicylate is also useful and may be more effective than loperamide when vomiting accompanies the diarrhea.
  • Adults with other serious medical problems and those with severe diarrhea (high fever, abdominal pain, or bloody stool) should see a health-care professional before using either medication.

Electrolyte solutions are available to prevent salt deficiency.

  • Oral electrolyte solutions are available at grocery and drug stores (Pedialyte, Rehydralyte, Naturalyte Solution).
  • Follow label directions, which may specify 1 teaspoonful every 15 minutes. If the child retains the initial doses, increase the dose to 1 tablespoonful every 15 minutes until the diarrhea stops.

What Is the Medical Treatment for Severe Diarrhea?

If a person has severe diarrhea, they should contact their doctor or go to an emergency department or urgent care center because medical treatment may be necessary.

To replace fluids, a health care professional will often start an IV line if the patient is dehydrated and can't eat or drink. IV solutions will replace the lost fluids and electrolytes and often brings quick relief. If the patient is able to drink, rehydration solutions may be given orally.

Diphenoxylate and atropine (Lomotil) is an anti-diarrheal medication that a doctor may prescribe.


Antibiotics will get not rid of diarrhea caused by viruses. Even the more severe diarrhea caused by bacteria will usually go away in a few days without antibiotics. Antibiotics appear to make some bacterial diarrhea worse, specifically those caused by the E coli bacterium (often a source of food poisoning).

In some cases, antibiotics may benefit some adults with diarrhea. If selected carefully, antibiotics may decrease the severity of illness and shorten the duration of symptoms. If a person has recently traveled to another country or has been camping (and may have been exposed to contaminated water in the wilderness), a health care professional may prescribe specific medication used to treat traveler's diarrhea for certain intestinal parasites.


If a person has severe diarrhea, especially accompanied with dehydration, he or she may require hospitalization to receive IV fluids and to be observed.

Is It Possible to Prevent Diarrhea?

Many cases of diarrhea are spread from person-to-person. The following precautions can help an individual avoid diarrhea and other viral or bacterial infections:

  • Individuals caring for sick children or adults in any setting should carefully wash their hands after changing diapers, helping an individual use the bathroom, or assisting an individual around the home.
  • Children should be instructed to wash their hands frequently, especially after using the bathroom.

Practice safe food handling. Always wash hands before and after handling food.

  • Use care when preparing raw poultry or meat. Food should be cooked to the recommended temperatures. Avoid raw or rare meat and poultry. Utensils coming in contact with raw food should be cleaned in soap and hot water.
  • Fruits and vegetables consumed raw should be thoroughly rinsed in clean water.
  • Unpasteurized (raw) milk may be contaminated with bacteria and should always be avoided. Unpasteurized fruit juice or cider should generally be avoided even if the source is not known because the fruit may have come in contact with contaminated animal feces in the orchard.
  • Use caution when traveling, especially to foreign countries. Do not eat foods from street vendors. Don't drink water or drinks with ice cubes made from tap water if the country is deemed unsafe. Check the Travelers' Health Web site of the Centers for Disease Control and Prevention for travel information for your destination.

What Is the Prognosis for Severe Diarrhea?

  • Drink plenty of fluids to avoid dehydration. Follow the advice of your doctor or health care professional.
  • If your diarrhea gets worse, or if you have a high fever, abdominal pain, or bloody stools contact your doctor.
  • Abdominal pain, cramping, and other problems should begin to improve 2-3 days after the original episode of diarrhea. You may have loose stools longer than other symptoms.
  • Health care professionals usually see serious and life-threatening diarrheal disease in people who become severely dehydrated, particularly infants, the elderly, people with compromised immune systems, or other people with significant medical illnesses.

Diarrhea: Is It the Stomach Flu?

The stomach flu, or medically referred to as gastroenteritis, can be caused by a variety of things like viruses, bacteria, fungi, inflammation from medications (antibiotics), seafood, food allergies, and heavy metals. Common symptoms of the stomach flu include:

  • Diarrhea
  • Nausea
  • Vomiting
  • Crampy abdominal pain
Reviewed on 7/22/2022
American Cancer Society. "Diarrhea." June 8, 2015. <http://www.cancer.org/treatment/treatmentsandsideeffects/physicalsideeffects/dealingwithsymptomsathome/caring-for-the-patient-with-cancer-at-home-diarrhea>.

Chiba, T., and S.F. Phillips. "Alcohol-related diarrhea." Addict Biol 5.2 Apr. 1, 2015: 117-125. <http://www.ncbi.nlm.nih.gov/pubmed/20575826>.

LaRocque, Regina, and Jason B. Harris. "Patient information: Acute diarrhea in adults (Beyond the Basics)." UpToDate. March 2019. <https://www.uptodate.com/contents/acute-diarrhea-in-adults-beyond-the-basics>.

LaRocque, Regina, and Jason B. Harris. "Travelers' diarrhea. Microbiology, epidemiology, and prevention." UpToDate. March 2019. <http://www.uptodate.com/contents/travelers-diarrhea-microbiology-epidemiology-and-prevention?source=search_result&search=traveler%27s+diarrhea&selectedTitle=2~60>.

Murao, Satoshi, and Hitoshi Hosokawa. "Serotonin 5-HT3 Receptor Antagonist for Treatment of Severe Diabetic Diarrhea." American Diabetes Association. Diabetes Care 33.3 March 2010: e38. <http://care.diabetesjournals.org/content/33/3/e38.full>.

Riddoch, C., and T. Trinick. "Gastrointestinal Disturbances in Marathon Runners." Brit J Sports Med 22.2 June 1988: 71-74. <http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1478552/pdf/brjsmed00038-0025.pdf>.

United States. National Cancer Institute. "Gastrointestinal Complications (PDQ) -- Health Professional Version." Nov. 28, 2018. <http://www.cancer.gov/about-cancer/treatment/side-effects/constipation/gi-complications-hp-pdq#link/stoc_h2_4>.

United States. National Institute of Diabetes and Digestive and Kidney Diseases. "Symptoms & Causes of Diarrhea." November 2016. <https://www.niddk.nih.gov/health-information/digestive-diseases/diarrhea/symptoms-causes>.

Wald, Arnold. "Factitious diarrhea." UpToDate. Apr. 1, 2019. <http://www.uptodate.com/contents/factitious-diarrhea>.