How and what causes ashma?

Airway inflammation: Asthma is caused by inflammation of the airways. This causes the caliber of the airway to be smaller, which produces the characteristic "musical sound" we call wheezing. This inflammation can be caused by outside irritants or by the body attacking itself. In either case, the treatment is much the same. Medications to open the airways and steroids to reduce inflammation.

Many things can: Sometimes, asthma happens for no known reason. It can also happen with irritants like smoke, pollen from plants, viruses that cause respiratory infections, allergies to airborne particles, allergies to other things, running or other exercise, changes in weather, certain medications, anxiety, etc... A patient with asthma symptoms should figure out her causes, so she can take medicine when needed.