Asthma symptoms are set off – or triggered – by airborne substances that initiate changes in the airways of sensitive people that then make it hard to breathe. These substances are called asthma triggers. They can be categorized in several ways.
One category of asthma trigger includes substances known as allergens. Allergens stimulate an allergic response, which is a type of immune system reaction, in your airways. Allergens fall into the following subcategories.
Tree, Grass, and Weed Pollen
Source: American Academy of Allergy, Asthma and Immunology
Pollen is an airborne allergen that may set off numerous asthma symptoms in sensitive people at certain times of the year. Pollen consists of tiny, egg-shaped male cells found in flowering plants. You may know pollen better as the tiny, powdery granules that plants use during the fertilization process.
Mold & Mold Spores
Photo © A.D.A.M.
Mold can be both an indoor and an outdoor asthma trigger, depending on where you find it. Outdoor molds are found in piles of dead leaves, soil, vegetation and rotting wood.
Animal Allergens
Photo Courtesy of Stock Xchange
Being around furry and feathered animals can trigger asthma symptoms in sensitive people. In fact, just being in an environment where an animal lives, even if they are not there at the same time as you, can be enough to set off asthma and allergy symptoms. It is commonly believed that an animal's hair is the allergen, but this is not true.
Dust Mites
Source: American Academy of Allergy, Asthma and Immunology
Dust mites, tiny creatures that are too small to be seen with the naked eye, live in house dust. They eat plant and animal material in the dust. The mites release droppings, and these droppings are the true reason why dust is such a common asthma trigger.
Insect Allergens
Source: Journal of Allergy and Clinical Immunology
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.
