Indoor triggers, which can be found in many forms and in every room, include cigarette smoke, dust, dust mites, foods, pollen, straw, feathers, hair, fibers, formaldehyde, sprays, pesticides, deodorizers, mold, fungus, pets, cockroaches, gas from stoves, garbage, and more than 250 known causative agents responsible for occupational asthma.

Indoor triggers are extrinsic (outside the body).

Mold Spores

Molds like to grow in dark, damp places such as your basement, garage, under the kitchen sink, in leaky pipes, in garbage pails, and even in vaporizers and humidifiers.

Dust Mites

Dust mites are tiny organisms that live in dust. They can be found almost everywhere indoors -- in carpet, bedding, upholstered furniture, stuffed toys and mattresses.

Animal Allergens

All furry and feathered animals shed dander, or tiny flakes of skin. The dander often mixes with dust and can stay around your house long after the animal is gone. Proteins in the dander can trigger asthma symptoms. These proteins are also found in animal urine, feces and saliva.

Cockroaches & Other Insect Allergens

Cockroaches and other insects can shed very potent allergens. Cockroaches like to live in dark, damp places, especially where there is open food. Certain stinging insects also can trigger life-threatening allergic shock reactions in people who have asthma.