Registered Nurses' Association of Ontario

Nursing Best Practice Guidelines

What Causes Asthma in Children?
  • The most common asthma trigger in children is viral infection.
  • Common asthma triggers include irritants (tobacco smoke, exercise, weather changes, outdoor pollutant and exposure to indoor chemical) and allergens (pollen, dust mite, pet dander, food or food additive).
  • An individual’s triggers may change over time.
  • Allergic rhinitis, sinusitis or gastroesophageal reflux may aggravate asthma.