Asthma and Airway Centre

The Asthma Education Handbook

Allergic Triggers

A "trigger" is something irritating to the airways causing asthma symptoms to occur. The airway muscles tighten, the lining becomes swollen and inflamed while mucus sticks to the airway wall. By trying to identify and avoid certain triggers, you can keep your asthma under control. An allergy skin test is helpful to identify allergic triggers. When your asthma is under control with medication, you may be less susceptible to triggers.

Trigger
Image: Pollen Source of Allergen
trees, grass, ragweed

Preventitive Measures

avoid freshly cut lawns
keep doors and windows closed in the relevent pollen season, use central air conditioner if available

Trigger
Image: Dust mite Source of Allergen
dust mites are found in carpets, furniture, mattresses, pillows, stuffed toys or dusty areas

Preventitive Measures

vacuum regularly, avoid sweeping
encase mattresses with dust mite proof coverings or use zippered vinyl encasings
use synthetic pillows and encase in dust mite proof coverings
do damp dusting regularly
change furnace filters as recommended
keep humidity in house less than 50% to reduce the number of dust mites

Trigger
Image: Mould Source of Allergen
damp areas (i.e. floors, sinks, bathrooms, laundry areas), in the soil of household plants, garbage cans or humdifiers outdoors moulds can be found in damp areas e.g. lawns, shrubs, garbage heaps

Preventitive Measures

clean regularly
avoid strong smelling detergent for household cleaning
reduce the number of house plants
clean humdifiers if used regularly
keep humidity in house less than 50% to reduce growth of mould

Trigger
Image: Animals Source of Allergen
dander (scales or dead cells) and saliva from cats and dogs, feathers from birds

Preventitive Measures

remove these from the home especially from the bed or bedroom if you have allergies to these (see section on Improving your Home Environment)

Trigger
Image: Foods Source of Allergen
certain foods (i.e nuts, shell fish, eggs, milk or chocolate, additives or food coloring), sulphite in dry preserved fruits, beer, wine or salads, monosodium glutamate (MSG)

Preventitive Measures

avoid known triggers
read labels on products
enquire if these are added to restaurant foods