Allergen. A substance, such as pollen, mold, dust mites, or animal dander, that can cause an allergic response.
Bronchoconstriction. A tightening of the muscles around the airways, narrowing the airways and making breathing difficult.
Inflammation. A swelling and irritation in the airways of the lungs common in asthma.
Inhaler. A device that delivers asthma medication to the lungs.
Mucus. A wet, sticky substance that is produced by the airways when inflamed or infected.
Peak flow. A measure of how hard and fast air can be expelled from the lungs.
Triggers, irritants or allergens, such as weather conditions, fumes, pollution or exercise, that can cause an asthma attack.
Wheezing. The whistling or squeaky sound created by the airways.