Asthma

Asthma Causes

What Causes Asthma?

The true cause of asthma, and why your lungs overreact to certain triggers, essentially a lung abnormality, is not yet known. Through research, scientists have established that the disease is a special type of inflammation of the airway that leads to the contraction of airway muscle, mucus production and swelling in the airways. Thus, the airways become overly responsive to environmental changes and the result is wheezing and coughing.

If your lungs and airways are oversensitive to certain triggers, asthma symptoms can be caused by breathing in allergy causing substances (called allergens or triggers – please click here to read our Key to Understanding Allergies page for more information).

Asthma triggers vary from person to person. Various factors can trigger symptoms of asthma by increasing airway hyper-responsiveness. These include:

Airborne allergens including animal dander, dust mites, mold, pollen
Air pollutants and irritants including tobacco smoke
Allergic reactions to foods
Allergic reactions to certain medications including aspirin and other non-steroidal anti-inflammatory drugs (NSAIDS)
Cold air
Exercise or physical activity (exercise-induced asthma)
Gastroesophageal reflux disease (GERD), a condition in which stomach acids back up into the throat
Infections such as the common cold, flu, or pneumonia
Respiratory infections including the common cold
Stress,anxiety and emotional behavior such as laughing or crying
Sulfites, preservatives added to some perishable foods
Weather, particularly extreme changes in temperature