Diarrhea

The stomach flu, the runs or “Montezuma’s revenge”: no matter what name you give it, diarrhea shouldn’t be taken lightly. Whether from a temporary infection or Crohn's disease, diarrhea can be controlled. Learn what to do when diarrhea hits.

What is diarrhea?

Diarrhea is characterized by an increase in the frequency, consistency  and volume of stool. More specifically, diarrhea refers to at least 3 liquid or soft stools in a 24-hour period.

Normally, only a very small amount of the fluids that we ingest every day is eliminated in the stool after passing through the intestines. Our body recovers almost all of this liquid and excretes most of it through the kidneys and bladder. When the intestines have trouble recovering this liquid, more is eliminated in the stool, which can cause diarrhea.

Diarrhea causes

Diarrhea has many causes. It can be a symptom of a health problem or food intolerance or allergy (e.g., lactose intolerance), or it can be a side effect of medication. Diarrhea can also occur from stress or anxiety . Although unpleasant, diarrhea can be very useful and even beneficial. For example, diarrhea is a mechanism that quickly eliminates viruses, bacteria or parasites in the intestines following an infection or food poisoning.

How to prevent diarrhea

Diarrhea has many causes. It can be a symptom of a health problem or food intolerance or allergy (e.g., lactose intolerance), or it can be a side effect of medication. Diarrhea can also occur from stress or anxiety . Although unpleasant, diarrhea can be very useful and even beneficial. For example, diarrhea is a mechanism that quickly eliminates viruses, bacteria or parasites in the intestines following an infection or food poisoning.

How to prevent diarrhea

A few simple rules will help you prevent infections and food poisoning that can cause diarrhea.

  • Wash your hands frequently, preferably with soap and water or, if these aren't handy, an alcohol-based hand sanitizer.
  • Avoid eating foods after their expiry date or foods that haven't been properly stored, such as buffet dishes that have been sitting out at room temperature for several hours. For more information on food safety, see the Food and Nutrition section of healthycanadians.gc.ca.

How to prevent traveller's diarrhea

If you’re travelling to a region where food and water safety standards aren't the same as at home, you need to take precautions to prevent traveller's diarrhea.

  • Before leaving on your trip, check with your pharmacist, your doctor, or a travel clinic about getting vaccinated for traveller's diarrhea and to find out which medications you should take with you.
  • Always use bottled or purified water for drinking and brushing your teeth.
  • Make sure that the ice cubes in your drinks are made from bottled or purified water.
  • Avoid eating raw fruits and vegetables, unless you’re sure that they have been cleaned with purified water or that you can peel them yourself.
  • Only eat food that is thoroughly cooked and served immediately.

When to consult a doctor about diarrhea

You should consult a doctor when:

  • Along with diarrhea, you have a fever above 38.5 °C, blood or mucus in your stool, or strong cramps.
  • Your stool is green or black.
  • The diarrhea lasts for over 5 to 7 days for adults, 48 hours for seniors, and 24 hours for children.
  • The child with diarrhea is under the age of 1, has a fever and is vomiting. 
  • You’re over 65 and have an existing condition (e.g., diabetes, Crohn's disease, ulcerative colitis, kidney failure, or a disorder that requires you to take lithium).
  • You're pregnant.
  • You have signs of dehydration:
    • loss of appetite, weight loss
    • dry skin, mouth or tongue
    • extreme thirst
    • unusual weakness, tiredness
    • hollow eyes, cheeks, abdomen
    • decreased tear production
    • less frequent urge to urinate or darker-coloured urine
    • in babies, fewer than 4 wet diapers in 24 hours or a dry diaper for over 3 hours

Diarrhea treatment

Below are some foods you can eat and foods to avoid when you get diarrhea. It is very important that you keep from getting dehydrated.

Foods to eat for diarrhea

Ever wonder what you can eat when you have diarrhea? You can try rehydration solutions, diluted juices, dry crackers, white toast, white rice, soup or broth. Instead of having 3  large meals during the day, you should also eat smaller amounts more often. Once you feel better, you should go back to eating a varied and balanced diet.

Foods to avoid when you have diarrhea:

  • Foods that contain a lot of sugar, fibre (berries, grains, oatmeal, oats), or fat, until your diarrhea goes away.
  • Irritants such as alcohol, coffee, tea, sugary drinks, flattened soft drinks, “sugar-free” products (with added sweeteners), chocolate and spicy foods.
  • Dairy products during the first 48 hours (does not apply to breastfed or bottle-fed infants).

Rehydration solutions

These solutions compensate for lost water and mineral salts caused by diarrhea and prevent dehydration. Examples of commercial preparations include Gastrolyte™ and Pedialyte™. A homemade solution can also do in a pinch if you can't get out to buy one.

Rehydration solutions are recommended for everyone, especially people most at risk of dehydration, such as children and seniors.

Drink small quantities of these solutions at a time and at regular and frequent intervals. For adults, the recommended amount is 30 ml to 90 ml (2 to 6 tablespoons) every 30 to 60 minutes up to a maximum of 2 to 3 litres in a 24-hour period. For children, the amount is determined by weight:  1 ml/kg every 5 minutes over a 4-hour period. If the diarrhea persists after this period, keep giving your child the same dose for another 4-hour period. 

Homemade rehydration solution recipe

  • 360 ml of unsweetened orange juice, without the pulp (and not juice crystals)
  • 600 ml of water boiled for 20 minutes and then cooled
  • ½ teaspoon of table salt

 Measure each ingredient precisely and mix together. Store unused portions in the fridge and make a fresh solution each day.

Medication

Over-the-counter medications can help treat diarrhea by keeping water out of the stool and slowing down intestinal contractions. These medications are not always recommended, particularly if you have a fever, which can be a sign of food poisoning or a microbe that needs to be flushed out of your system. Talk to your pharmacist, who can help you choose the best medication for your health condition.

Probiotics

Probiotics are good bacteria that live in our intestinal flora and play a role  in the health of our digestive system. Probiotic supplements, which are available over the counter, can help prevent and treat some types of diarrhea, such as diarrhea caused by antibiotic treatment. Antibiotics kill a particular bacteria causing an infection, but they also destroy good bacteria in the intestinal flora, which causes diarrhea. Ask your pharmacist which type of probiotics are best for you.

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