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Diarrhea and vomiting

Published on April 12, 2024 at 8:00 / Updated on May 1, 2024 at 8:00

Diarrhea is the passage of three or more loose or watery stools within 24 hours in adults and children, and an increase in stool frequency to twice the usual number per day in infants. Infections, illnesses and medications can all cause diarrhea.

Gastroenteritis, a highly contagious and very common infection, is an inflammation of the stomach and intestines. Most at risk are young children, older adults and persons with weakened immune systems.


Gastroenteritis is caused by viruses, bacteria or parasites. It is spread through direct and indirect contact, or eating foods handled by an infected person.


Symptoms last from 1-3 days but can persist for 7-10 days. They include:

  • Diarrhea, nausea, vomiting
  • Abdominal cramping
  • Low-grade fever
  • Headache
  • Muscle aches
  • Fatigue

When to seek help

Most cases do not require medical attention. See a doctor however, if you have:

  • Diarrhea or vomiting for more than 48 hours or that is frequent and profuse
  • Inability to drink or keep fluids down
  • Fever (higher than 38°C) for more than 48 hours
  • Bloody or black stools
  • Severe abdominal pain
  • Signs of dehydration (thirst, decreased urination, muscle cramps, sunken eyes, dizziness, lack of tears in a crying infant)
  • Weakness, drowsiness, irritability, confusion
  • Diarrhea during or after trip abroad


Gastroenteritis causes the body to eliminate significant amounts of water and essential mineral salts. The goal of treatment is to prevent dehydration. Adults can drink broths, sports drinks and diluted fruit juices. Rehydration solutions are a good alternative in severe cases. Avoid alcohol, caffeine, soft drinks and undiluted fruit juices.

Eating is important. Start with small portions and eat throughout the day. Increase portions gradually based on tolerance. Saltine crackers, soup, rice, noodles and bananas are good options.

In young children, consider eating habits:

  • Continue to breastfeed. If the child can only ingest small amounts, nurse more often.
  • If not breastfeeding, continue to feed smaller amounts of milk more often.
  • Older children should eat based on their likes and tolerance. Avoid juices, soft drinks and Gatorade-type beverages.
  • If there are signs of dehydration, give small amounts of fluids often. Offer more than just plain water. If the child vomits breastmilk or is not breastfed, use an oral rehydration solution.


Opt for commercial rehydration solutions (Pedialyte®, Gastrolyte®). If unavailable, make your own.

Respect the exact quantities. Do not substitute any ingredient without first speaking to a health professional. This solution can be stored for 12 hours at room temperature or 24 hours in the refrigerator:

Cooled boiled water2½ cups (600 mL)
Unsweetened orange juice1½ cups (360 mL)
Table salt½ teaspoon (2.5 mL)
Total4 cups

When diarrhea is present, rehydration solutions should be started quickly. Use the table below as a guideline:

AgeAmount to administer
NON-breastfed child
0-6 months30-90 mL/hour
6-24 months90-125 mL/hour
> 2 years125-250 mL/hour


To prevent the spread of gastroenteritis, wash hands with soap and water frequently. Decontaminate surfaces with bleach (toilet, handles). When possible, avoid direct contact with infected persons.

The drugs and pharmaceutical services featured on the website are offered by pharmacists who own the affiliated pharmacies at Familiprix. The information contained on the site is for informational purposes only and does not in any way replace the advice and advice of your pharmacist or any other health professional. Always consult a health professional before taking or discontinuing medication or making any other decision. Familiprix inc. and the proprietary pharmacists affiliated with Familiprix do not engage in any way by making this information available on this website.