top of page

Gastroenteritis advice and management tool


What is Gastroenteritis?

  • Gastroenteritis is a condition that causes irritation and inflammation of the stomach and intestines (the gastrointestinal tract). The most common symptoms are diarrhea, crampy abdominal pain, nausea, and vomiting.

  • By definition, gastroenteritis affects both the stomach and the intestines, resulting in both vomiting and diarrhea.

  • Many people also refer to gastroenteritis as "stomach flu." This can sometimes be confusing because influenza (flu) symptoms include headache, muscle aches and pains, and respiratory symptoms, but influenza does not involve the gastrointestinal tract.

  • The term stomach flu presumes a viral infection, even though there may be other causes of infection.


What causes Gastroenteritis?

Viral infections are the most common cause of gastroenteritis but bacteria, parasites, and food-borne illnesses can also be the cause.

The severity of infectious gastroenteritis depends on the immune system's ability to resist the infection. Hence those at most risk are infants and the elderly. Electrolytes (these include essential elements of sodium and potassium) may be lost as the affected individual vomits and experiences diarrhea.


How long will my child be sick?

Most people recover easily from a short episode of vomiting and diarrhea by drinking fluids and gradually progressing to a normal diet. But for others, such as infants and the elderly, loss of bodily fluid with gastroenteritis can cause dehydration, which could become a life-threatening illness unless the condition is treated and hydration is restored.


Is it contagious?

  • Yes, via the fecal-oral route.

  • Hence the importance of good effective hand-washing and sanitizing especially after changing sick infants and toddlers or handling soiled clothing or diapers.

  • The child needs to be free from diarrhea (and vomiting) for at least 48hours to be cleared.


Is there a medicine available to protect my child from this illness?

  • There is a vaccine, Rotarix or RotaTeq, against the most common virus Rotavirus, which is administered during the routine vaccination schedule only in infancy.

  • The current recommendation is 2 separate doses of Rotarix or 3 separate doses of RotaTeq to patients aged 6-32 weeks.

  • Antibiotics are generally not used.


How will I know this is what my child has?

  • Viral gastroenteritis typically presents with low-grade fever (up to 100°F, 38°C) and vomiting followed by watery diarrhea (up to 10-20 bowel movements per day), with symptoms persisting for 3-8 days.

  • Bacterial gastroenteritis is more likely to be associated with high fevers, shaking chills, abdominal cramping, and bloody bowel movements (dysentery).


Does my child need investigations?

  • The vast majority of children presenting with acute gastroenteritis do not require any laboratory tests in hospital. However if your doctor believes your child is significantly dehydrated or has evidence of systemic infection expect investigations to be done.


How do I manage this at home?

  • Since most causes of gastroenteritis are due to viruses, replacing the fluid lost because of vomiting and diarrhea allows the body to recuperate and fight the infection.

  • In general, children with gastroenteritis should be returned to a normal diet as soon as possible.

  • Early feeding reduces illness duration and improves nutritional outcome.

  • Our practice offers to our patients HYDRATION INSTRUCTIONS briefly outlined at the bottom of this information sheet to know how much feed and fluid to give your child and for how long.

  • The general principal early in the illness is to offer small frequent offerings of clear fluids, sometimes only a mouthful at a time.

  • If you are breastfeeding continue to do so but more frequently and for longer periods each feed.

  • Clear fluids (anything you can see through), may be tolerated in small amounts.

  • Think of it as adding just an ounce or less to the saliva that the child is already swallowing.

  • However, giving too much fluid at one time may cause increased nausea.

  • Clear fluids do not include carbonated beverages but colas or ginger ale with the fizz gone is often well tolerated in older children.

  • Jello and popsicles may be "solid food" alternatives to clear fluids in children who aren't interested in clear fluids.

  • Oral rehydration therapy using balanced electrolyte solutions such as Pedialyte or Gatorade/Powerade are advised.

  • Plain water is not recommended because it can dilute the electrolytes in the body.

  • Once your child is drinking (and eating) their usual amounts and seems better in themselves you should resume their normal diet:

    • If your child is formula fed, restart feeding with the same formula at full strength.

    • If your child is weaned, restart their normal fluids and solids as soon as you can.

    • However, fatty foods and very sugary foods are best avoided for at least the duration of time the child is ill.

    • There is no evidence to support lactose-free formulas over lactose-containing formulas after gastroenteritis nor highly specific diets including the BRAT (bananas, rice, applesauce, and toast) diet and they may in fact provide suboptimal nutrition for the patient.


If you are managing your child at home:

  • Are you unable to orally rehydrate your child or provide adequate care at home?

  • Are you having difficulties administering oral rehydration (e.g. constant vomiting or inadequate intake)?

  • Do you think your child is getting worse?

  • Are you worried or concerned?

If so consult a physician immediately


Does your child:

  • appear more lethargic, lifeless, drowsy or difficult to rouse from sleep despite attempts to rehydrate them?

  • pass less urine now than yesterday?

  • have sunken eyes?

  • have an absence of tears?

  • have little or no saliva in their mouth?

  • display a slow return of the skin to flat after you gently pinch the skin of the tummy?

  • have worsening abdominal pain?

  • have a fever >101°F (40°C)?

  • still having diarrhea now 2 weeks after it began?

If so take your child to hospital immediately.




Key Point: hydration is more important than nutrition.


A guide to small frequent oral rehydration:

  • Offer 1/3 of an ounce (5 to 10ml) of fluid at one time. Wait 5 to 10 minutes then repeat.

  • If this amount is tolerated without vomiting, increase the amount of fluid to 2/3 of an ounce (10 to 20ml). Wait and repeat.

  • If tolerated, increase the fluid offered to 1 ounce (30ml) at a time.

  • If vomiting occurs, go back to the 1/3 of an ounce (5 to 10ml) and restart.

  • Once the child is tolerating significant fluids by mouth, a more solid diet can be offered.




Canadian Pediatric Society


bottom of page