Chronic Diarrhea: Definition, Types, Symptoms, Causes and Treatment

It is an increase in the frequency of bowel movements, an increase in stool looseness or both.

Diarrhea is caused by increased secretion of fluid in the intestine, reduced absorption of fluid from the intestine or rapid passage of stool through the intestine.

Symptoms associated with diarrhea include abdominal pain, especially cramping. Other symptoms depend on the cause of the diarrhea.

Diarrhea can be defined absolutely or relatively. Absolute diarrhea is defined as more than five bowel movements per day or liquid stools.

Relative diarrhea is defined as an increase in the number of stools per day or an increase in stool looseness compared to an individual’s usual bowel habit.

Diarrhea can be acute or chronic, and each has different causes and treatments.

Complications of diarrhea include dehydration, electrolyte (mineral) abnormalities, and irritation of the anus.

Tests that are useful in assessing acute diarrhea include stool examination for white blood cells or enzymes that produce, parasites, stool cultures for bacteria, stool analysis to determine C toxins. Blood tests to detect electrolyte abnormalities .

Tests that are useful in the evaluation of chronic diarrhea include the stool test for parasites, upper gastrointestinal radiographs.

Barium enema, esophagus-gastro-duodenoscopy (EGD) with biopsies, colonoscopywith biopsies, endoscopy of the small intestine with biopsies, breath test of hydrogen, measurement of fat in the stool and pancreatic function tests.

Dehydration can be treated at home with home remedies, oral rehydration solutions.

Absorbents (which absorb water in the intestine), antimotility drugs, bismuth compounds and intravenous fluids if necessary.

Antibiotics should not be used in the treatment of diarrhea unless there is a bacterial infection proven by culture that requires antibiotics.

Severe diarrhea that is probably of infectious origin, or that an individual has serious underlying diseases.

What is considered diarrhea?

Diarrhea can be defined in absolute or relative terms depending on the frequency of bowel movements or the consistency (looseness) of bowel movements.

Frequency of bowel movements:

Absolute diarrhea has more bowel movements than normal. Therefore, since among healthy people, the maximum amount of daily bowel movements is approximately three.

Diarrhea can be defined as any amount of stools greater than three, although some consider that five or more bowel movements are diarrhea. “Relative diarrhea” is having more stools than usual.

Therefore, if an individual who usually has a bowel movement each day begins to have two bowel movements per day, then the relative diarrhea is present, even if there are no more than three or five bowel movements per day, that is, there is no absolute abscess. .

Stool consistency:

Absolute diarrhea is more difficult to define about the consistency of the stools because the consistency of the stools can vary considerably in healthy individuals depending on their diets.

Therefore, people who eat large amounts of vegetables will have looser stools than people who consume few vegetables and / or fruits.

Stools that are liquid or watery are always abnormal and are considered diarrheic. Relative diarrhea is easier to define depending on the consistency of the stool.

Therefore, an individual who develops softer stools than usual has relative diarrhea, even if the stool may be within the range of normality with respect to consistency.

Why does diarrhea develop?

With diarrhea, stools are usually weaker, regardless of whether the frequency of bowel movements is increased. This looseness of the stool, which can vary from slightly soft to watery, is caused by the increase of water in the stool.

During normal digestion, food is kept liquid by the secretion of large amounts of water by the stomach, the upper small intestine, the pancreas and the gallbladder.

The food that is not digested reaches the small intestine and the colon in liquid form. The lower small intestine and particularly the colon absorb water, converting undigested food into a more or less solid fecal matter.

Larger amounts of water may be produced in the stool if the stomach and / or small intestine secrete too much fluid, the distal small intestine and colon do not absorb enough water, or the undigested liquid foods pass too quickly through the small intestine and the intestine. colon for enough water to be removed

Another way to see the reasons for diarrhea is to divide it into five types:

  1. The first is known as secretory diarrhea because too much fluid is secreted in the intestine.
  2. The second type is known as osmotic diarrhea in which small molecules that pass into the colon without being digested and absorbed extract water and electrolytes into the colon and stool.
  3. The third type is known as motility-related diarrhea in which the intestinal muscles are overactive and transport intestinal contents through the intestine without sufficient time to absorb water and electrolytes.
  4. The fourth type is unusual. It is best represented by a condition called collagenous colitis. In collagenous colitis, the mechanism of diarrhea may be the inability of the colon to absorb fluids and electrolytes due to extensive scarring of the intestinal lining. Inflammation can also play a role.
  5. The fifth type of diarrhea is known as inflammatory diarrhea and involves more than one mechanism.

For example, some viruses, bacteria and parasites cause a greater secretion of fluid, either by invading and inflaming the lining of the small intestine (inflammation stimulates the lining to secrete fluid) or by producing toxins (chemicals).

They also stimulate the coating to secrete fluid but without causing inflammation.

Inflammation of the small intestine and / or colon by bacteria or by non-bacterial ileitis / colitis can increase the speed with which food passes through the intestines, reducing the time available to absorb water.

Diarrhea is usually divided into two types, acute and chronic

Acute diarrhea lasts from a few days to a week.

Chronic diarrhea can be defined in several ways, but usually lasts more than three weeks.

It is important to distinguish between acute and chronic diarrhea because they usually have different causes, require different diagnostic tests and require different treatment.

Symptoms of chronic diarrhea

The symptoms associated with chronic diarrhea depend on the cause and type of diarrhea.

If there is a large secretory component for diarrhea, bowel movements are frequent and aquatic. Pain is not common and there are no signs of inflammation.

Similarly, an osmotic diarrhea is watery, but its main characteristic is that once the food intake is stopped (which would include the food or substance that is not digested or absorbed) the diarrhea stops.

Diarrhea related to motility is more likely to be associated with abdominal cramps.

Inflammatory diarrhea is often associated with crampy abdominal pain as well as signs of inflammation, for example, fever and abdominal tenderness.

It can also be associated with intestinal bleeding, either with blood visible in the stool or invisible blood that is only detected when analyzing the stool for blood.

Although one might expect the diarrhea of collagenous colitis to be painless as it is believed that diarrhea is due to poor absorption of fluids and electrolytes.

In fact, it is frequently associated with abdominal pain, which suggests that there is more collagenous colitis that lacks fluid and electrolyte absorption.

What are the most common causes of chronic diarrhea?

The most common cause of chronic diarrhea is a viral, bacterial and parasitic infection. Bacteria can also cause acute food poisoning.

A third important cause of diarrhea is to start a new medication since many medications can cause diarrhea.


During mild cases of diarrhea, diluted fruit juices, soft drinks containing sugar, sports drinks such as Gatorade, and water may be used to prevent dehydration.

Caffeine and lactose that contain dairy products should be temporarily avoided as they can aggravate diarrhea, the latter mainly in people with transient lactose intolerance.

If there is no nausea and vomiting, solid foods should continue. Foods that are generally well tolerated during a diarrheal disease include rice, cereals, bananas, potatoes and lactose-free products.

Oral rehydration solutions can be used for moderately severe diarrhea that is accompanied by dehydration in children older than 10 years and in adults.

These solutions are administered at 50 ml / kg for 4-6 hours for mild dehydration or 100 ml / kg for 6 hours for moderate dehydration.

After rehydration, the oral rehydration solution can be used to maintain hydration from 100 ml to 200 ml / kg for 24 hours until the diarrhea ceases.

The instructions on the solution label usually indicate the amounts that are appropriate. After rehydration, older children and adults should resume solid foods as soon as nausea and vomiting subside.

Solid food should start with rice, cereals, bananas, potatoes and lactose-free and low-fat products. The variety of foods can expand as diarrhea decreases.

What home remedies help the symptoms of diarrhea?

Many home remedies have been suggested for the treatment of diarrhea, however, few of them have been well studied. Three that have been studied and appear to be effective are:

  • Pectin.
  • Cooked green bananas.
  • Probiotics