Causes of Asthma

The cause of asthma is not yet understood. Both genetic and environmental factors appear to play roles in asthma. Many people with asthma have allergic reactions to particles breathed in through the air, such as animal dander and pollen. These common substances are called allergens, meaning that they cause an allergic reaction. The tendency to react to allergens by having an asthma attack is probably genetic. There is no cure for asthma, although it can be controlled by learning to avoid asthma triggers and by taking medicine.