What are the main causes of diarrhea?

Many cases of diarrhea are due to an infection or disruption of the gastrointestinal tract.Common causes of acute diarrhea include:

• food poisoning
• viral gastroenteritis
• medicine side effects

Chronic diarrhea

Conditions such asirritable bowel syndrome (IBS) are a common causes of “functional” chronic diarrhea. This means that although all the digestive organs appear normal, they are not functioning as they ideally should.

Some other major causes of chronic diarrhea include:

• Microscopic colitis: This is a persistent type of diarrhea that usually affects older adults. It develops due to inflammation and occurs often during the night.
• Malabsorptive and maldigestive diarrhea: The first is due to impaired nutrient absorption, and the second is due to impaired digestive function.Celiac disease is one example.
• Chronic infections:A history of travel orantibiotic use can be clues in chronic diarrhea. Various bacteria and parasites can also be the cause.
• Drug-induced diarrhea: Laxatives and other drugs, including antibiotics, can trigger diarrhea.
• Endocrine-related causes: Sometimes, hormonal factors cause diarrhea. This is the case inAddison’s disease and carcinoid tumors.
• Cancer-related causes:Neoplastic diarrhea is associated with a number of gut cancers.

Quiz

How can a person treat diarrhea?

Mild cases of acute diarrhea may resolve without treatment. For persistent or chronic diarrhea, a doctor will treat any underlying causes in addition to the symptoms of diarrhea.

The sections below will discuss some possible treatment options for getting rid of diarrhea in more detail.

Rehydration

Replacing the fluids, salts, and sugars lost during diarrhea is vital for all cases. However, children and older people are atgreater risk ofdehydration.

Oral rehydration solution or salts (ORS) can be particularly effective in dehydration recovery. ORS refers to water that contains salt and glucose. The small intestine absorbs the solution to replace the water and electrolytes lost in the stool. In developing countries, ORS costs just a few cents.

Antidiarrheal medication

Over-the-counter antidiarrheal medications are also available. These includeloperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol).

Imodium is an antimotility drug that reduces stool passage. Pepto-Bismol reduces diarrheal stool output in adults and children. It can also prevent traveler’s diarrhea.

Antibiotics

Antibiotics can only treat diarrhea due to bacterial infections. If the cause is a certain medication, switching to another drug might help.

Always talk with a doctor before switching medications.

Diet

The following diet tips may help with diarrhea:

• sipping on clear liquids, such as electrolyte drinks, water, or fruit juice without added sugar
• after each loose stool, replacing lost fluids with at least 1 cup of liquid
• doing most of the drinking between, not during, meals
• consuming high potassium foods and liquids, such as diluted fruit juices, potatoes without the skin, andbananas
• consuming high sodium foods and liquids, such as broths, soups, sports drinks, and salted crackers
• eating foods high in soluble fiber, such as banana, oatmeal, and rice, as these help thicken the stool
• limiting foods that may make diarrhea worse, such as creamy, fried, high dairy, and sugary foods

Foods and beverages that might make diarrhea worse include:

• sugar-free gum, mints, sweet cherries, and prunes
• caffeinated drinks and medications
• fructose in high amounts, from fruit juices, grapes, honey, dates, nuts, figs, soft drinks, and prunes
• lactose in dairy products
• magnesium
• olestra (Olean), which is a fat substitute
• anything that contains artificial sweeteners

Learn more about foods to eat with diarrhea here.

Symptoms

Diarrhea refers to watery stools, which may be accompanied by other symptoms. These include:

• stomach pain
• abdominal cramps
• bloating
• weight loss
• fever
• body aches
• chills

Diarrhea is also a symptom of other conditions, some of which can be serious. Other possible symptoms are:

• blood orpus in the stool
• persistent vomiting
• dehydration

If any of these accompany diarrhea, or if the diarrhea is chronic, it may indicate a more serious illness.

Complications

Two potentially seriouscomplications of diarrhea are dehydration (in cases of severe and frequent diarrhea) andmalabsorption (in cases of chronic diarrhea).

Diarrhea can also indicate a wide range of underlying chronic conditions. Diagnosis and treatment can help prevent further problems.

Tests and diagnosis

When diagnosing the cause of diarrhea, a doctor will ask about the person’s symptoms and:

• any current medications they take
• their past medical history
• their family history
• their travel history
• any other medical conditions they have

They will also ask:

• when the diarrhea started
• how frequent the stools are
• if blood is present in the stool
• if the person has been vomiting
• whether the stools are watery or contain mucus or pus
• how much stool there is

They will also look for signs of dehydration. Severe dehydration can be fatal if the person does not receive rehydration therapy immediately.

Tests for diarrhea

Most cases of diarrhea resolve without treatment, and a doctor will often be able to diagnose the problem without the use of tests.

However, in more severe cases, a stool test may be necessary — especially if the symptoms persist for longer than a week.

The doctor may also recommend further tests if the person has:

• signs of fever or dehydration
• stools with blood or pus
• severe pain
• low blood pressure
• a weakened immune system
• recently traveled
• recently received antibiotics or been in the hospital
• diarrhea persisting for longer than 1 week

Further tests

If a person has chronic or persistent diarrhea, the doctor will order tests according to the suspected cause.

These may include:

• A full blood count: Anemia may suggest malnutrition, bleeding ulcerations, or IBD.
• Liver function tests: These will include testing albumin levels.
• Tests for malabsorption:These will check the absorption ofcalcium,vitamin B-12, andfolate. They will also assess iron status and thyroid function.
• Erythrocyte sedimentation rate and C-reactive protein:Raised levels may indicate IBD.
• Tests for antibodies: These may detect celiac disease.
• Stool tests: Doctors can identify parasites, bacteria, and a few viruses in stool cultures. Stool tests can also reveal microscopic blood, white blood cells, and other clues for diagnosis.

When should a person be concerned about diarrhea?

In most cases, diarrhea isn’t something to be concerned about and will resolve itself without medical treatment. However, it is important to seek medical help when there is:

• persistent vomiting
• persistent diarrhea
• dehydration
• significant weight loss
• pus in the stool
• blood in the stool, which may turn the stool black if it is coming from higher up in the gastrointestinal tract

Anyone who experiences diarrhea after surgery, after spending time in the hospital, or after using antibiotics should seek medical attention.

Adults who lose sleep due to diarrhea should also seek medical care as soon as possible, as this is usually a sign of more serious causes.

How long is too long for diarrhea?

If a person has diarrhea and it lasts for more than7 days, they should consult a doctor urgently.

Additionally, caregivers should take infants to see a doctor as soon as possible if they have hadmore than five bouts of diarrhea or vomited more than twice within 24 hours.

Prevention

The following can help prevent diarrhea:

• drinking clean and safe water only
• having good sanitation systems, such as wastewater and sewage
• having good hygiene practices, such as regularly washing the hands with soap, especially before preparing food and eating and after using the bathroom
• educating oneself on the spread of infection

There is evidence to suggest that interventions from public health bodies to promote hand-washing can reduce diarrhea rates by aboutone-third.

In developing countries, however, the prevention of diarrhea may be more challenging due to dirty water and poor sanitation.

Summary

Diarrhea is a common problem with many potential causes.

In most cases, a range of home remedies and medical treatments can help. However, a person should see their doctor if they are concerned about diarrhea or other symptoms.

How we reviewed this article:

Share this article