A common condition experienced by almost everybody at some point in their lives, diarrhea is the passage of loose, watery stool. Each year, there are about 2 billion cases of diarrhea and diarrhea-related diseases globally. Diarrhea is the leading cause of mortality in children four years of age and younger worldwide, with most mortalities occurring in patients from developing countries. In the United States, acute diarrhea is the second most commonly reported illness, following respiratory infections. Most cases of diarrhea are mild, though uncomfortable, and typically clear up within a few days.

Diarrhea can also be referred to as diarrhoea, dysentery, the runs, the trots.

What is Diarrhea?

Diarrhea is the increased frequency of bowel movements consisting of loose and watery stool. This condition can present suddenly, and typically lasts a few days. Diarrhea can affect people of all ages, although infants, children, and the elderly are at the highest risk for complications due to the dehydration caused by diarrhea.

Absolute diarrhea is the passage of five or more bowel movements per day of liquid stool, while relative diarrhea is an increase in the usual number of bowel movements, especially if abnormally loose and watery, experienced by a particular person.

Although some people may experience frequent bowel movements, this is typically not considered diarrhea, unless the stool is observed to be abnormally loose and watery.

Acute diarrhea is diarrhea that lasts less than 2 weeks. Acute diarrhea attacks typically are short – between a few hours to a couple of days, of three or more irregularly loose and watery stools within a 24 hour period. Conditions such as cholera are classified as acute diarrhea. When acute diarrhea produces bloody stool, it is known as dysentery.

Persistent diarrhea lasts between 2 and 4 weeks.

Chronic diarrhea is diarrhea that lasts longer than 4 weeks.

What Causes Diarrhea?

Diarrhea presents when fluid is not fully or efficiently absorbed by your colon, or there is an increased secretion of fluid into the intestine, thus resulting in watery stool. It may also occur after increased motility of the intestines, or due to inflammation along the lining of the intestines.

Osmotic diarrhea describes the condition that occurs when the small intestine cannot adequately absorb a soluble compound, leading to fluid being taken into the gut.

Secretory diarrhea occurs after chloride is actively secreted into the bowels. This causes diarrhea due to the passage of water, which follows the chloride ions, and resulting in a loss of fluid.

Most cases of diarrhea are caused by an infectious virus, parasite, or bacteria that contaminates the gut. The majority of acute diarrhea cases are caused by such infections. Chronic diarrhea may have other, underlying causes, such as an intestinal disease or malabsorption of fats.

Some cases of diarrhea caused by bacteria and parasites are known as Traveler’s Diarrhea (also known as Cruise Ship Diarrhea), which is often contracted when traveling to or visiting another country, typically a developing or third-world country. Exposure to unsafe, unclean water or food is usually the root cause of Traveler’s Diarrhea.

Viruses that may induce diarrhea include the Norwalk virus, rotavirus, cytomegalovirus, and viral hepatitis.

Parasites, such as Giardia lamblia or cryptosporidium may induce diarrhea.

Common diarrhea-causing bacteria found in the United States are Salmonella, Campylobacter, Shigella, and Escherichia coli.

Some people contract diarrhea through contact with contaminated food or water, pets carrying infections, or contaminated fecal matter. Other causes of diarrhea include:

  • Alcohol abuse
  • Allergies
  • Diabetes
  • Intestinal diseases – Crohn’s disease, ulcerative colitis, celiac disease, microscopic colitis, irritable bowel syndrome
  • Pancreatitis
  • Food poisoning
  • Overuse or abuse of laxatives
  • Use of certain medications – antibiotics, NSAIDs, antacids, antihypertensives, antiarrhythmics
  • Consuming foods or food additives that may trigger an episode of diarrhea – such as fructose, artificial sweeteners (sorbitol, mannitol), sugar-free candies (gum, mints), Olestra (a fat substitute)
  • Lactose intolerance
  • Hyperthyroidism
  • Radiation therapy
  • Running or extreme physical activity (sometimes referred to as “Runners diarrhea,” “Runners trots,” or “the gingerbread man”)
  • Certain cancers
  • Surgery or other medical procedures involving the digestive system – including abdominal surgery, gallbladder removal surgery
  • Malabsorption
  • Following constipation

Patients with a family history of celiac disease, inflammatory bowel disease, or other intestinal diseases may be more likely to develop cases of diarrhea.

Diagnosing diarrhea typically involves a consultation with your medical provider, and includes an evaluation of your recent history and a physical examination. Sometimes, a stool or blood sample may be useful to determine the exact cause of the diarrhea, such as the specific parasite, bacteria, virus, or toxin. Other medical techniques for diagnosing diarrhea include a colonoscopy, or imaging tests such as an X-ray or CT scan. Imaging tests are useful in that they help to identify or rule out other conditions or internal abnormalities that might be causing the diarrhea.

Signs and Symptoms of Diarrhea

Diarrhea can most often be identified due to the loose, watery stool, and frequent bowel movements. Common symptoms of diarrhea include:

  • Runny or watery stool (stool that “takes the shape of the container”)
  • Thin or loose stool
  • Dehydration
  • Loss of appetite
  • Frequent and urgent bowel movements
  • Irritation of the rectal area
  • Nausea
  • Vomiting
  • Bloating
  • Thirst
  • Weight loss
  • Cramping
  • Abdominal pain
  • Blood in the stool
  • Fever
  • Chills

Symptoms typically last only a few days, and usually clear up on their own, although strong viruses can persist for up to 10 days. Consider speaking with a medical provider if symptoms persist or worsen.

Prevention of Diarrhea

Because acute diarrhea is often caused by parasites, bacteria, or viruses that are passed through contact, it is important to maintain frequent hand-washing practices to minimize the spread of such contaminants. Hand washing is important particularly after handling raw meats, using the toilet, changing diapers, sneezing, coughing, or blowing your nose. If possible, use soap and water. Hand sanitizer or an alcohol-based hand rub is an adequate substitute if soap and water are unavailable, although soap and water are preferred.

To further decrease risk of contamination through infected surfaces and objects, it is helpful to frequently wash and disinfect surfaces such as kitchen counters and thoroughly wash fruits and vegetables. Food that has been prepared should be served immediately or placed in the refrigerator, to discourage bacterial growth. Frozen meats and foods should be thawed in the refrigerator.

When traveling, be aware of your new environment and surroundings. Check travel alerts that include warnings for maintaining health and avoiding certain contaminants, especially if traveling outside of the United States. The Centers for Disease Control is a reliable source for such information. If possible, try to eat well-cooked and hot foods and drink bottled beverages. Try to keep your mouth closed during showers, and brush your teeth with bottled water. If using tap water, boiling it can help reduce the chance of contamination spreading. Consider speaking with a medical provider for prophylactic medications or antibiotics that reduce the risk of Traveler’s Diarrhea.

Some people have found that consuming probiotics helps cultivate an environment of healthy bacteria within your gut, that can help fight off infectious particles. Probiotics can be obtained through supplements, and also found in cheese and yogurt.

Eating a healthy diet that contains fiber can help thicken your stool and reduce the chance of diarrhea. Avoiding or minimizing consumption of high-fat, creamy, fried, or sugar-filled foods also helps reduce the occurrence of diarrhea.

Some infants and children, particularly those at high risk, may also benefit from the rotavirus vaccine (RotaTeq, Rotarix), to protect from possible infection. Another vaccine that has been studied to decrease the occurrence of diarrhea include the measles vaccine.

Mothers with young infants are advised to breastfeed for the first 6 months of a baby’s life, as this may help prevent diarrhea.

Treatment of Diarrhea

Most cases of diarrhea will usually clear up on their own, without treatment, or with over-the-counter and home treatments.

Often, rest and hydration will help clear out diarrhea symptoms. Avoiding exercise and strenuous physical activity helps prevent dehydration. Liquids such as water, sports drinks with electrolytes, fruit juice without pulp, broth, soda without caffeine, and tea with honey are helpful ways to stay hydrated during an episode of diarrhea. Children may benefit from an electrolyte drink such as Pedialyte. Try to avoid fluids that contain caffeine or alcohol. If a patient has experienced severe fluid loss or is extremely dehydrated, a medical team may administer intravenous (IV) fluids to compensate for the loss. Oral rehydration solutions also provide relief from dehydration.

Common over-the-counter medications that help relieve diarrhea symptoms include:

  • Bismuth subsalicylate (Pepto-Bismol, Kaopectate)
  • Loperamide (Imodium)
  • Absorbents
  • Anti-motility medications

Diarrhea caused by bacteria may warrant an antibiotic prescribed by your medical provider. After an initial consultation and possibly some lab tests, your medical provider can more efficiently determine the cause of your diarrhea. Diarrhea caused by a virus will not be helped with an antibiotic.

To ease any stomach pain and help the stomach recover from an episode of diarrhea, eating bland and solid foods may provide relief. Common food plans include the BRAT diet, which includes bananas, rice, apples, and toast. Other foods include eggs, soda crackers, or chicken. Avoid semisolid foods, foods containing fiber, dairy products, fatty foods, or foods containing a lot of seasoning until your diarrhea symptoms subside.

Irritation, pain, burning, or itchiness in your rectal area may occur due to the frequent bowel movements associated with diarrhea. To relieve some of these symptom, consider taking a warm bath and patting the affected area dry with a clean and soft towel. Alternatively, hemorrhoid cream or white petroleum jelly may provide relief.

Though uncommon, some cases of untreated diarrhea can lead to more serious conditions and complications, including dehydration, electrolyte imbalances, and irritation of the rectal area. Consider speaking with a medical provider if your diarrhea symptoms do not subside within a few days.

Diarrhea caused by another illness, particularly a chronic intestinal condition, may need further evaluation for treatment and development of an appropriate long-term care plan. Your medical provider may refer you to a gastroenterologist or other specialist.

Although not scientifically proven, some patients have found diarrhea relief through herbal remedies. Such therapies include:

  • Blackberry, blueberry, and raspberry tea leaves – these contain tannins that many believe help provide diarrhea relief
  • Chamomile tea
  • Acupressure
  • Aromatherapy

When Should I Call a Doctor?

You should seek medical attention right away if you notice blood appearing in your stool, or if you become extremely dehydrated in combination with your symptoms of diarrhea. Symptoms of severe dehydration include:

  • Dry mouth
  • Dry skin
  • Excessive thirst
  • Lack of urine
  • Extremely dark-colored urine
  • Severe weakness
  • Lethargy
  • Dizziness

Contact a medical provider if you are also experiencing the following symptoms in addition to your diarrhea:

  • Persistent and high fever (higher than 101 F)
  • Severe abdominal pain
  • Severe rectal pain
  • Black, tar-like (color and consistency) stool
  • Nausea (especially if unable to take in fluids)
  • Vomiting (especially if unable to take in fluids)
  • Feelings of irritability or confusion
  • Headaches
  • Rapid heart rate

If your diarrhea has lasted for more than a few days with no relief, it is best to speak with a medical provider.

Additionally, if you are returning from travel having experienced Traveler’s Diarrhea, an evaluation by a medical provider can help ensure further complications do not arise.

Elderly patients, pregnant women, and patients with conditions such as diabetes, heart disease, kidney disease, liver disease, HIV/AIDS should seek medical care when experiencing diarrhea to reduce the possibility of serious complications.

Babies and children experiencing diarrhea should be evaluated by a medical professional, as this can develop into a serious problem, and warrants different treatment than adult patients suffering from this condition. Other symptoms seen in children experiencing diarrhea that warrant medical attention include:

  • Diarrhea symptoms not improving within 24 hours
  • If the child has not had a wet diaper in three hours or longer
  • Dry mouth, crying with no tears
  • Persistent and high fever (higher than 101 F)
  • Black, tar-like (color and consistency) stool
  • Bloody stool
  • Uncharacteristically sleepy, irritable, or unresponsive
  • If the child has a “sunken” appearance in the abdomen, eyes, or cheeks
  • If the skin does not flatten out if pinched and subsequently released