Welcome to our new website!

Welcome! We hope you find our new website helpful and easier to navigate. It's now as easy to use on your smartphone as your desktop. Take a tour and please tell us what you think.

Asthma

Asthma is a chronic (life-long) disease where the airways in the lungs are inflamed and narrowed, making it hard to breathe. It’s normal for airways to get mildly inflamed and narrow when exposed to smoke, pollution, and other irritants. However, children and youth with asthma get very narrow airways because of exposure to things they are sensitive to that shouldn’t irritate the lungs, like pollen or even the common cold. 
Did you know: asthma is the most common chronic disease in children? More than 1 out of 10 children will have asthma at some point in their life.

What you need to know

  • Asthma is a common chronic condition in children and youth 
  • Asthma inflames and narrows airways, making it hard to breathe
  • With proper treatment, children and youth can live normal active lives 

Types of asthma: 

Viral-triggered Asthma: Some children are born with smaller airways. When they catch a cold, the airways get swollen, inflamed, and much narrower, making it much harder to breathe. These children will often outgrow their asthma. 

Allergic asthma: Children with allergies sometimes develop allergic asthma. They have asthma symptoms when exposed to allergens such as dust, pollen and animal fur. They also have symptoms when they catch a cold and often with exercise. These children are less likely to outgrow their asthma. 

Asthma symptoms may include: 

  • Cough that is excessive compared to others
  • Wheezing (high-pitched whistling noise when breathing out)
  • Difficulty breathing or chest tightness 

Ask yourself: 

  • Can my child keep up with others while running around?
  • Do they have a hard time catching their breath?
  • Do they cough more at night or cough so hard they vomit? 

Triggers: The first step of asthma therapy is to avoid triggers when possible. The most common trigger in children is the common cold. Other triggers include smoke, pollution, and allergens like dust mites, pollen, and animal dander. 

Medications: There are two types of inhaler medications used to control asthma symptoms: relievers and controllers. 

Reliever (rescue) medications: 

  • Work quickly to relax airway muscles
  • Used when breathing is difficult
  • Ventolin® works within 5 minutes and lasts 4 hours. Can be used for up to every 4 hours during illness. The child or youth must see a health care professional if they need their rescue medication for more than 4 hours. They can also be taken 15 minutes before exercise
  • Oxeze® or Serevent are long-acting bronchodilators, used on a long-term basis in conjunction with an inhaled steroid controller medication (see below). Oxeze® starts working 5 minutes; Serevent starts working in 30 minutes. Both last 12 hours.  

Inhaled Sterid Controller medications: 

  • Reduce inflammation of the airways
  • Take 1–6 weeks to start working
  • Must be taken every day
  • Not effective for acute attacks 

Examples include Flovent®, Alvesco®, Pulmicort®, Asmanex® 

  • Use with a spacer device to prevent thrush and improve delivery
  • May slightly affect growth (monitor with doctor)
  • May require cortisol monitoring when used in high doses
  • May cause thrush (rinse mouth after use) 

Other medications: 

  • Singulair®: non-steroid anti-inflammatory pill or sprinkle; takes up to 3 weeks. Side effects: headache, stomach aches, behaviour changes 

Combination inhalers: 

  • Symbicort®, Advair, Zenhale®
  • Provide long-term control and improved lung function
  • Taken twice daily; Symbicort® may also be used during attacks (for a maximum of 8 puffs/day) 

Proper inhaler technique is essential to ensure medication reaches the lungs. 

How to prepare

Avoid triggers: 

  • Do not smoke near the child (including in the home or car)
  • Instruct your child or youth to wash or sanitize their hands before touching their nose or mouth to help prevent catching viral infections
  • Get annual flu vaccination
  • Check air quality (Air Quality Health Index) 

Reduce allergens in the home (if your child or youth is allergic to these things): 

  • Dust Allergy: Use dust-mite proof covers, reduce clutter, vacuum regularly, keep humidity level under 50%
  • Pollen Allergy: Keep windows closed during pollen season; use air conditioning
  • Animal Allergy: Limit animal exposure; keep pets out of bedrooms; consider an air purifier in the child’s bedroom
  • Mold Allergy: Clean mold with soap and water; use ventilation; seek professional help for large areas contaminated with mold, keep humidity level under 50%
  • Cockroach Allergy: Use professional exterminators for cockroaches and keep child away during treatment 

Aftercare / What to do at home

  • Reduce exposure to triggers  

  • Continue daily controller medications as prescribed

  • Use reliever inhaler as needed for symptoms

  • Monitor symptoms and triggers

  • Ensure proper inhaler technique 

  • If your child or youth has a fever, give acetaminophen (Tylenol®, Tempra®) or ibuprofen (Advil®, Motrin®)
  • Do not give ibuprofen to babies under six months of age 

Watch for dehydration

  • Babies under age 2 should have at least four wet diapers a day
  • Children older than age 2 should pee 3–4 times per day
  • Signs of dehydration include peeing less than 50% of their normal amount, being very sleepy, or having very dry lips 

Feed your child

  • Your child may not want to eat solid foods for a few days — this is OK
  • The most important thing is to keep them well hydrated
  • If your child is eating, you can continue to offer food
  • Most children return to their normal diet within a day or two 

✓ My child has diarrhea (without vomiting) 

Diarrhea means watery stools (poop) that happen more often than usual. It takes time for the bowel to heal, so stools may stay soft for up to ten days after the diarrhea. These guidelines apply to children of any age. 

Replace fluids using breast milk or clear fluids 

If you are breastfeeding:

  • Breastfeed often to replace fluids lost through diarrhea
  • If your child eats solid foods, slowly return to their normal diet 

If you are not breastfeeding: 

  • Slowly return to their normal diet, such as formula or milk
  • Staying hydrated Staying hydrated is very important when your child is sick.
  • Children with mild dehydration can be hydrated with clear fluids (such as diluted apple juice or diluted ginger ale), or oral Rehydration Solutions (ORS) such as Gastrolyte® or Pedialyte®
    • Are made with the right balance of sugars, salts, and water
    • Are available in most drug stores
    • Come in different flavours and taste better cold or frozen into popsicles 

* Speak to a nurse if the cost of ORS will be difficult for your family. 

Call 8-1-1 to speak with a 24/7 nurse, or your family doctor or go to the Emergency Department if your child: 

  • Symptoms are not well controlled
  • You have questions about medications or inhaler use 

Go to the Emergency Department if: 

  • Needing reliever medication more than every 4 hours  

    • Severe shortness of breath 

  • Rapid, shallow breathing
  • Skin sucking in at the neck or ribs
  • Blue skin
  • Severe cough or wheezing returning within 4 hours
  • Unable to speak in full sentences
  • Extreme fatigue or fainting 

Print as a PDF fact sheet

Disclaimer 

These resources are for educational purposes only. If you have questions, speak with your health care provider. Last updated: June 2026

Have you registered for MyChart?

MyChart is a free, secure, online patient portal that connects patients to parts of their CHEO electronic health record, anywhere, at any time. 

MyChart