What is Diarrhea?
Diarrhea can be described as frequent, loose, watery stools. It means you have a lot more bowel movements than what you would consider “normal”. For most people this means more than three loose watery movements in 24 hours. (1)
Diarrhea is also referred to as the runs, the trots and dysentry.
There are estimated to be about 179 million cases of diarrhea in the US each year. (2)
Whatever the cause and no matter how long it lasts diarrhea can be incapacitating.
Causes
Diarrhea may be acute and last a couple of days, persistent and last two to four weeks or chronic and last more than four weeks.
The causes of acute and persistent diarrhea may be different from those associated with chronic diarrhea.
For example, acute diarrhea may go away within a few days and you might never even know the cause of it. (3)
We will detail some the causes of diarrhea divided into their respective categories – acute or chronic.
Acute and Persistent Diarrhea
This type of diarrhea is usually caused by an infection or reaction to medication. Travellers’ diarrhea is also classed as acute. (4)
Infections
There are three types of infection that can cause diarrhea. They are viral, bacterial and parasitic.
Most of these are transmitted by what is called the fecal oral route. This means that the virus passes from the faeces into the mouth via food, people or infected surfaces. (5)
There are many viruses that cause diarrhea. The most common ones are norovirus and rotavirus.
Norovirus
Norovirus causes gastroenteritis or stomach flu. This causes inflammation of the stomach and intestines. This in turn causes diarrhea.
It can be spread through food and water or from person to person. If you touch a surface like a door handle which is contaminated you can catch the virus. The same applies when you transfer the virus via food etc. to your mouth. (6)
This virus is sometimes called the cruise ship virus. It appears to have earnt notoriety from outbreaks on these holiday vessels. It is not contained to cruise ships. Outbreaks of this viral infection are common throughout the food service industry. (7)
Rotavirus
This is another virus that causes gastroenteritis. It is prevalent in babies and young children. In fact almost every child in the US below the age of five will most likely catch this virus at some point.
Due to the amount of children infected by this virus there is now a vaccine available to help prevent it. (8)
This virus causes diarrhea and vomiting that lasts about three to eight days. (9)
Parasites
A parasite is a tiny organism that lives inside another one. It can harm the host in some way or live at the expense of the host. (10)
Parasites that can cause diarrhea include cryptosporidium, entamoeba and guardia.
Cryptosporidium causes diarrhea in all age groups. It can be dangerous for people who have weakened immune system.
This parasite lives in both contaminated public water supplies or contaminated pools and lakes. Unpasteurized cider also contains this parasite. (11)
The infection from entamoeba is called amoebiasis. This parasite causes acute dysentery or long-term diarrhea.
The infection can also spread through the bloodstream to the liver. It can spread to the lungs, brain, or other organs, but this is rare.
Outbreaks have been linked with food or water contaminated with stools. The parasite is also in fertilizer made of human waste.
It can also be passed from person to person. This is more likely if you have contact with the mouth or rectal area of an infected person. (12)
Giardia infects the small intestine and is called giardiasis. It causes diarrhea.
This parasite lives in soil, food, and water. Surfaces that come into contact with animal or human waste can also house this bug.
Infection can be passed on by family members with giardiasis. Raw or undercooked food can also be contaminated with the parasite.
The parasite is prevalent in care homes and daycare centres. It can also be contracted from having unprotected anal sex.
Animal watering holes like streams and lakes can be infected. Domestic and wild animals leave their waste there when they drink. (13)
Bacteria
Some bacteria like e.coli and salmonella can cause diarrhea. It may be persistent or chronic. (14)
Travellers Diarrhea
This is the most common illness contracted when travelling, especially to underdeveloped countries. Infections, bacteria or parasites come from infected food or water.
This type of diarrhea is usually acute. Some parasites can make it last longer. (15)
Side Effects of Medicines
Certain medication can cause diarrhea as a side effect. The types of medicines responsible include antibiotics, antacids containing magnesium and cancer treatments. (16,17,18)
Chronic Diarrhea
Chronic diarrhea lasts for 4 weeks or more. This type of diarrhea is usually associated with an underlying medical condition. Use of various medications on a long term basis can upset the intestines. It can also be caused by infections. (19)
Infections
Some of the bacteria and parasites we have mentioned can also cause chronic diarrhea. They don’t always go away as quickly as we would like.
One of the side effects of this prolonged diarrhea can be malabsorption. This means the small intestine cannot take in nutrients the body needs from food. This includes carbs, protein, fats and vitamins and minerals. (20)
Food Allergies or Intolerances
Allergies or intolerance to certain foods can cause chronic diarrhea.
Many people can be lactose intolerant. Lactose is found in milk and milk based products. Gas, bloating and diarrhea are all possibilities after consuming them. (21)
Fructose is a sugar found in fruits, juices and honey. It is also added to many soft drinks as a sweetener. Some vegetables and processed or marinated meats also have a high fructose content.
Intolerance causes diarrhea, bloating gas and stomach pain. (22)
Sugar alcohols are more commonly known as sweeteners. They can be found in many products including food, drinks, cosmetics and chewing gum. Intolerance can cause diarrhea. (23)
Digestive Conditions
There are many medical conditions associated with the digestive system. They include irritable bowel syndrome, celiac disease, crohn’s disease and colitis.
Diseases of the digestive system can cause diarrhea. (24)
Abdominal Surgery
Some people experience diarrhea after abdominal surgery. This can follow an operation on any part of the digestive system. (25)
Long Term Medication
There are over 700 drugs that can cause diarrhea. The effects could be felt in the first few days of taking the drug, or it may take weeks to show up. (26)
Long term use of antibiotic drugs can leave you susceptible to gut infections. This causes chronic diarrhea. (27)
Symptoms
The main symptom of diarrhea is loose, watery, stools. You will also find your need to visit the bathroom becoming more urgent and frequent.
You could experience cramps and pain in the stomach. Nausea and sickness can also accompany diarrhea. You might even lose control of your bowels.
Some infectious types of diarrhea may make you feel light headed and dizzy. You can have a fever or chills. Your stools can contain blood and you can vomit. (28)
One of the side effects of diarrhea is dehydration. This can leave you feeling light headed or faint. Your urine may be dark and infrequent. You will feel thirsty and have a dry mouth.
If not addressed this can cause further problems, particularly in children and infants. You need to make sure that you consume lots of fluids to replace what is being lost. (29)
If your diarrhea persists for more than 2 days and you think you are dehydrated you need to seek urgent medical advice. Especially if you have a fever, stomach or rectal pain and vomiting.
Diagnosis
Many of us who encounter short term diarrhea do not seek medical help. It passes in a day or two and we may never know the cause.
However, if you need to see a doctor they will ask about your symptoms. They will want to know how long you have had diarrhea. They need to know how frequently you are passing stools and what they are like.
Further useful information would be things like your family history and frequency of bouts of diarrhea. The types of food you eat and drink could give an indication of an intolerance.
A change of diet can be suggested to see if symptoms improve.
Other important factors are any medical conditions you have and medications you are taking. You might have been in contact with someone who is sick or have recently travelled to developing countries.
A physical examination will include taking your blood pressure and pulse. A doctor will also check for signs of dehydration. They will examine your abdomen.
They may check your anal passage to see if there is blood in your stools.
There are other tests that can be done to determine the cause of diarrhea. These include stool tests, blood tests and endoscopy. An endoscopy involves putting a camera in your body to help find the cause.
There are tests for food intolerance. A doctor may ask you to avoid certain foods like wheat or milk to see if your symptoms improve. These are called fasting tests.
There is also a test for lactose intolerance called a hydrogen breath test. High levels of hydrogen can indicate this intolerance. (30)
FAQ
What is diarrhea? Diarrhea is the frequent passing of loose, watery stools. Generally this is 3 or more a day.
What causes diarrhea? There are many causes for this condition. Some are short lived but some also persist. The causes can be due to infection, bacteria or parasites. They may also be food intolerances or an underlying medical condition.
How do doctors test for diarrhea? There is not an actual test for diarrhea but rather tests to find the causes. These include a physical examination, blood tests, stool tests, endoscopy and tests for food intolerances.
When should you go to the doctors with diarrhea? If your symptoms are severe from the outset you require emergency medical assistance. Otherwise if your diarrhea last more than 2 days you should see your doctor. Especially if you have signs of dehydration, a fever, blood in your stools and/or abdominal or rectal pain.
Can you prevent diarrhea? Some types of diarrhea can be prevented. There is a vaccine available for rotavirus which is usually given to babies. Travellers diarrhea can be prevented by only drinking bottled water when you travel. Also use it for making ice and cleaning your teeth. Avoid unwashed and unpeeled fruit and vegetables. Make sure any hot food is cooked properly. When travelling and at any other time make sure you thoroughly wash your hands with soap and water. Good hygiene can help prevent diarrhea.(31)
What can relieve diarrhea? There are over the counter medications that can help relieve the symptoms of diarrhea. A bland diet and plenty of fluids can also speed your recovery.(32)
Is diarrhea contagious? Certain types of diarrhea are contagious. Specifically infectious, bacterial and parasitic. If you have been in contact with someone who has this type of diarrhea good hygiene is important. (33)
What foods cause diarrhea? We have already learnt some food intolerances can cause diarrhea. Foods not stored and prepared properly can also cause this complaint. Make sure you cook foods thoroughly and eat them straight away. Don’t leave them out at room temperature where bacteria can grow. Make sure you sanitize food preparation areas well. (34)
Summary
Diarrhea is where your bowel movements become overly regular and very loose in consistency. It can be acute, persistent or chronic.
We have learnt diarrhea can be caused by many things. These include viruses, bacteria and parasites. There may also be underlying medical conditions.
Having diarrhea is not a pleasant experience. Fortunately for many it is short lived.
If you have chronic diarrhea there are things you can do to help. Food intolerance can be controlled by avoiding the triggers.
Dehydration can be a result of having diarrhea. If it is accompanied by other symptoms it can be dangerous and emergency care is needed.