Diarrhea is defined as the emission of watery, semi-formed or liquid stools several times a day and, in any case, more frequently than usual. Based on its duration, it can be divided into:

  • acute, if it lasts less than 2 weeks
  • chronic, if it is present for about 4 weeks

It happens to many people to suffer from it from time to time and, usually, it is not worrying. Nonetheless, it can be annoying and unpleasant until it ends and this usually happens within a few days or a week. There are various causes that cause diarrhea, among these, the most common, both in adults and children, is an intestinal infection (gastroenteritis).

Gastroenteritis can be caused by:

  • virus, such as norovirus and rotavirus
  • bacteria such as campylobacter and Escherichia coli, often contained in contaminated food
  • parasites, such as giardia, transmitted to humans through contaminated water

Intestinal infections can also be contracted while traveling abroad, particularly in areas with poor hygiene. This type of diarrhea is known as traveler's diarrhea.

Acute diarrhea it can also be associated with a food intolerance, a real allergy, the use of drugs or an anxious state. In some cases, the recurrence of episodes of acute diarrhea (recurrent diarrhea) can be linked to a chronic disease of the bowel such as, for example, irritable bowel syndrome (IBS). Chronic diarrhea it is often a sign of bowel inflammation.

After the last episode of diarrhea, it is advisable to stay home at least 48 hours to prevent the spread of the infection to other people.

Most cases of diarrhea heal after a couple of days even without treatment and, generally, it is not necessary to see the family doctor. However, it is advisable to drink plenty of fluids, even in small sips, because diarrhea can lead to dehydration. This occurs with particular frequency in the elderly who must, for this reason, be the subject of the same attention that is reserved for children. The family doctor may suggest that both adults and children at risk of dehydration use a oral rehydration solution.

If you have diarrhea, you can continue to eat solid foods, or start eating them again, if you feel able to do so. In infants, breastfeeding should not be interrupted, whether it is at the breast or with a bottle.

Medicines, such as loperamide, are available that limit diarrhea. Their use, however, is not recommended because diarrhea represents the mechanism put in place by the body to eliminate the infectious agent. The attending physician will be able to advise if and when to resort to these drugs which, for the most part, should not be given to children.

You should consult your doctor if diarrhea episodes are particularly frequent, severe or associated with other disorders (symptoms):

  • fever
  • blood and / or pus in the stool
  • He retched persistent
  • severe stomach pain or continuous
  • signs of dehydration such as drowsiness, passing small amounts of deep yellow or amber colored urine, feeling lightheaded or dizzy, disorientation in the elderly
  • dark colored stools or black, a possible sign of bleeding in the stomach
  • weight loss

It is advisable to contact the doctor in cases where, in both adults and children, diarrhea is particularly persistent because it could be the sign of a more serious problem that must be discovered and investigated. In most cases, the diarrhea should go away within a week or so.

Preventing diarrhea

Diarrhea is often caused by an infection. You can reduce your risk of getting sick by maintaining high levels of hygiene:

  • wash your hands thoroughly with warm soapy water after going to the bathroom and before eating or preparing food (Video)
  • clean the toilet, including the handle and seat, with disinfectant after each bout of diarrhea
  • avoid sharing towels, napkins, cutlery, glasses with other family members

It is also important to pay attention to hygiene in the intake of food and water when traveling abroad, avoiding drinking tap water because it is potentially unsafe, using ice in drinks and eating undercooked foods.


Diarrhea is a frequent production of watery, semi-formed or liquid stools. Some people may also have other disorders (symptoms), depending on the cause that determined it. Disorders (symptoms) associated with diarrhea can include:

  • belly cramps
  • stomach cramps
  • nausea and vomit
  • headache
  • loss of appetite
  • fever

Signs of dehydration

In children, dehydration can manifest itself with:

  • irritability or sleepiness
  • poor urine output. In infants, the amount of urine is considered low when more than three hours elapse between one urination (urination) and the next. Children and adolescents can spend up to eight hours or more without urinating if they are dehydrated.
  • poor lacrimation with crying
  • skin pallor with sunken eyes
  • cold hands and feet
  • worsening of general conditions

In adults, signs of dehydration can include:

  • thirst
  • dry mouth and kneaded
  • dry skin and not very elastic
  • sunken eyes
  • tiredness and lack of energy
  • loss of appetite
  • nausea
  • feeling lightheaded
  • dizziness
  • muscle cramps
  • rapid heartbeat

In severe cases, delirium and loss of consciousness may be present.

When to see your doctor

If the following complaints occur, the attending physician should be contacted as they could be a sign of important illnesses:


  • six or more episodes of diarrhea in the last 24 hours
  • three or more episodes of vomiting in the last 24 hours
  • diarrhea and vomiting at the same time
  • liquid stools
  • blood in the stool
  • a severe or ongoing stomach pain
  • signs of dehydration
  • diarrhea persistent (chronic diarrhea)


  • blood in the stool
  • persistent vomiting
  • consistent weight loss
  • large amounts of diarrhea very watery
  • episodes of diarrhea during the night that disturb sleep
  • appearance of diarrhea during or after antibiotic therapy or hospital treatment
  • symptoms of dehydration
  • dark colored stools or black because they could be signs of bleeding in the stomach

You should also contact your family doctor in case of persistent diarrhea (chronic diarrhea). Most diarrhea in adults heals within two to four days.


Diarrhea occurs when drinks and the liquid part of food cannot be absorbed by the intestine or when too much fluid passes into the intestine producing watery stools.

Acute diarrhea

Diarrhea that occurs suddenly and rapidly (acute diarrhea) is usually a symptom of an intestinal infection (gastroenteritis), which can be caused by:

  • virus, such as noroviruses and rotaviruses
  • bacteria, such as campylobacter, clostridium difficile (C. difficile), Escherichia coli (E. coli), salmonella or shigella which can cause foodborne infection
  • parasites, such as intestinal giardia which causes giardiasis

Other possible causes include:

  • anxiety
  • excessive alcohol consumption
  • food intolerance or presence of a real food allergy
  • appendicitis
  • damage caused by radiotherapy to the lining of the intestine
  • medications

Sometimes diarrhea can be an unwanted effect (side effect) caused by certain medications:

  • antibiotics for the treatment of infections
  • antacids containing magnesium for the treatment of gastritis and gastroesophageal reflux
  • chemotherapy for the treatment of tumors
  • non-steroidal anti-inflammatory drugs (NSAIDs)
  • serotonin reuptake inhibitors (SSRI from English selective serotonin reuptake inhibitors) normally used in the treatment of depressive states
  • statins to reduce cholesterol
  • laxatives to promote bowel emptying

The information on the package leaflet contained in the medicine pack must state whether the medicine includes diarrhea among its undesirable effects (side effects).

Chronic diarrhea

The causes that can determine diarrhea that persists over time (chronic diarrhea) are:

  • irritable bowel syndrome (IBS), a widespread disease that affects the motor functions of the intestine. In this case, diarrhea is more often recurrent
  • inflammatory bowel diseases, like Crohn's disease and ulcerative colitis, cause "inflammation of the gut"
  • celiac disease, a disease caused in some people by the ingestion of foods containing gluten
  • malabsorption of bile acids, occurs when the bile produced by the liver is not adequately reabsorbed by the intestine and accumulates inside it producing a laxative effect
  • chronic pancreatitis, inflammation of the pancreas which leads to a reduction in the production of digestive enzymes and, consequently, the malabsorption of undigested foods by the intestine with the production of diarrhea
  • diverticular disease consisting in the formation of sacs along the colon in which the stool accumulates and stagnates causing repeated (recurring) diarrhea
  • bowel cancer, the presence of a tumor in the colon may be associated with frequent episodes of diarrhea and, sometimes, with the presence of blood in the stool
  • consequences of surgical interventions on the gastrointestinal tract (gastric resection, intestinal resection, colon resection)


Most cases of diarrhea improve and heal within a week. If this does not happen, it is advisable to contact your family doctor who, to identify the causes, may prescribe some laboratory and instrumental tests and ask some questions:

  • appearance of stool, presence or absence of blood, watery or semi-solid consistency
  • frequency of discharges of diarrhea
  • presence of fever
  • any contact with people who had diarrhea
  • recent trips abroad
  • Possibility of contracting a food-borne infection from eating outside the home
  • any changes in therapy
  • presence of anxiety or stress

Stool examination

To identify signs of infection, the family doctor may order a stool test in the presence of:

  • persistent diarrhea that has lasted for more than two weeks
  • blood or pus in the stool
  • general ailments, such as fever or dehydration
  • weakened immune system, as can happen, for example, in people infected with human immunodeficiency virus (HIV)
  • recent trips abroad
  • recent visits to hospitals or consumption of antibiotics

Blood analysis

The family doctor, if he suspects that the diarrhea is caused by an inflammatory bowel disease, may prescribe some blood tests in addition to the stool test. Based on the results of the investigations, if he still has doubts about the causes of the diarrhea, he can recommend to contact a specialist for further investigations.

Rectal examination

It consists in the "introduction, by the doctor, of a finger inside the anus to explore the walls of the final part of the intestine (called straight) and identify any anomalies.

The examination usually precedes the execution of an endoscopic examination, called a sigmoidoscopy or colonoscopy, based on the part of the intestine that it explores, which allows you to see the walls of the colon. The endoscopic examination is performed by inserting a thin and flexible tube of variable length into the colon, equipped with a light source and a small camera that allows you to see the walls of the intestine in contact with the stool. During the investigation, thanks to the presence of one or more channels for the insertion of forceps or other tools, small parts (samples) of tissue (biopsies) can be taken to further ascertain (diagnose) the causes of diarrhea. It is also possible to carry out small operations (operative colonoscopy) such as the removal of polyps. The choice between sigmoidoscopy (exploration of the last tract of the colon) and colonoscopy (exploration of the entire colon) is at the discretion of the specialist based on the cause that he suspects is at the basis of the diarrhea.


Diarrhea usually ends without cure after a few days, particularly if it is caused by an infection.

In children, it typically disappears within five to seven days and rarely lasts longer than two weeks. In adults, it usually improves within two to four days, although some infections can last a week or more.

While waiting for the diarrhea to pass, it is possible to alleviate the symptoms by following some precautions:

Drink liquids

It is important for both adults and children to drink plenty of fluids in small sips to avoid dehydration, particularly if vomiting is present. If you drink enough, your urine will be light yellow or very clear.

Fruit juices or fizzy drinks should be avoided in children as they can make diarrhea worse. Breastfeeding must not be interrupted, whether it occurs at the breast or with the bottle (read the Bufala).

Use oral rehydration solutions

To prevent or treat dehydration, your family doctor or pharmacist may suggest that elderly or weak people drink some rehydrating solutions, consisting of sachets to be dissolved in water, to counteract the loss of liquids and mineral salts caused by diarrhea.


Oral rehydration solutions (SROs) can also be used in children if the pediatrician deems it appropriate because he fears that a state of dehydration may occur, or detects that it is already in progress. The dose and method of administration will vary according to the weight of the child and the severity of the diarrhea.

In case of dehydration, the child should not be given any solid food until he has drunk enough fluids. When there are no more signs of dehydration, normal nutrition can be resumed. If he refuses to eat, it is better not to force him, continue to give him fluids and wait for his appetite to return.


The opinions of experts on the foods to consume in case of diarrhea are different. However, most agree that light solid meals (e.g. boiled potatoes and carrots, rice, bananas) should be preferred as soon as they feel able to eat and that they should continue drinking. liquids.Salty foods are very useful in counteracting the loss of salts. Instead, greasy or spicy foods should be avoided.

Antidiarrheal drugs

Antidiarrheal medications can help reduce diarrhea and shorten its duration somewhat. However, diarrhea usually heals without the need to use them. Some antidiarrheal drugs can be purchased at a pharmacy without a prescription but, before taking them, it is advisable to carefully read the package leaflet that accompanies the package to find out if they are suitable for your case and what dose to take. If you are unsure, it is advisable to ask your doctor or pharmacist for advice. Antidiarrheal medications, however, unless prescribed by the treating physician, should not be taken if a fever is present or if blood or mucus appears in the stool. Also, in most cases, they shouldn't be used in children. Above three months of age, if the pediatrician deems it useful, medicines based on the active ingredient racecadotril combined with oral rehydration solutions can be used to prevent dehydration.

Loperamide is the main antidiarrheal drug used. It works by slowing bowel movements to promote greater absorption of the water contained in the stool. This makes the stool firmer and the bouts of diarrhea less frequent.

In addition to loperamide, another antidiarrheal drug is available, racecadotril, which works by reducing the amount of water produced by the small intestine.

Pain relievers

Painkillers such as, for example, paracetamol or ibuprofen, do not cure diarrhea but can help relieve the fever and headache that sometimes accompany it. pediatrician if the patient is a child, who will assess whether they are necessary or not, and will indicate in what doses and for how long to use them.However, it is advisable to carefully read the package leaflet in the package to get useful information on any contraindications or side effects that may occur.
Children under 16 should not be given aspirin.


Antibiotics are not recommended to treat diarrhea if its cause is unknown. These medicines, in fact:

  • they don't work if the diarrhea is caused by a virus
  • they can cause unpleasant side effects (side effects)
  • they can become less effective for treating infections if they are used incorrectly (for example, using them for viral diseases, taking them in doses and times not sufficient to kill the germs, stopping the treatment at the first signs of improvement instead of continuing it for the time indicated by the doctor) because the microbes could become resistant to their action

The attending physician can prescribe an antibiotic treatment, in case of severe diarrhea, where it has been ascertained the presence of a specific type of microbes or the reduction of the body's defense systems (immune system).

Hospital care

Sometimes hospitalization may be necessary when an adult or child is severely dehydrated. Treatment will include giving fluids and nutrients directly into a vein (intravenously).

Rotavirus vaccination

Rotavirus is a virus that commonly causes diarrhea in children. There is a vaccine that helps protect them against rotavirus and is available in Italy on a voluntary basis. It is given in liquid form in the baby's mouth. For information regarding age and methods of recruitment, it is necessary to contact your trusted pediatrician.

Treating the causes of diarrhea

If a specific disease is causing the diarrhea, treating it will help improve symptoms:

  • irritable bowel syndrome (IBS) can be cured with medications and dietary modifications
  • chronic inflammatory diseases of the intestine they can be treated with specific drugs that reduce inflammation
  • celiac disease it can be cured by excluding foods containing gluten from the diet
  • malabsorption of bile acids it can be treated with drugs that bind bile acids reducing their accumulation in the intestine

Prevention and Living with

To prevent the spread of infections that cause diarrhea, high standards of hygiene should always be maintained:

  • wash your hands thoroughly with warm soapy water after going to the bathroom and before eating or preparing food
  • clean the toilet, including the handle and seat, with disinfectant after each bout of diarrhea
  • avoid sharing towels, napkins, cutlery, glasses or utensils with the others
  • wash dirty clothes and bed sheets separately from other clothes and at the highest possible temperature (60 ° C, the highest temperature for the laundry) after removing all traces of feces by flushing them in the toilet
  • avoid returning to work, or school, until at least 48 hours after the last episode of diarrhea

Food hygiene

Practicing good hygiene will help avoid suffering from diarrhea caused by food poisoning. The following hygiene rules are recommended:

  • wash hands, surfaces and utensils regularly with warm soapy water
  • never store raw and cooked food together
  • make food safe by keeping it properly refrigerated
  • always cook food thoroughly
  • eat packaged food within the expiration date on the packaging do not eat raw food if you do not have guarantees on its preparation

Traveler's diarrhea

There is no vaccination that can protect against all possible causes of traveler's diarrhea.The best way to avoid being affected, when you are in foreign countries whose hygiene levels are unknown, is to observe some precautions:

  • do not drink tap water. To make it drinkable, the water must be boiled for at least one minute
  • do not eat ice cubes and ice cream
  • do not eat raw or undercooked seafood, meat and chicken not cooked thoroughly
  • do not eat foods that may contain raw eggs, such as mayonnaise
  • do not eat unpasteurized milk and dairy products
  • do not eat fruit with damaged peel
  • do not eat salads or raw vegetables

It is generally safe to eat or drink:

  • well cooked food and served hot
  • water in sealed bottles, carbonated drinks in sealed bottles or cans, alcohol
  • personally peeled fruit and vegetables
  • hot tea or coffee

If you are planning a trip abroad, it is advisable to consult the reference center of the National Health Service closest to your city.

In-depth link

NHS. Diarrhoea and vomiting (English)

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