Asthma is a condition caused by constriction of air passages in the lungs. The exact cause is unknown, but likely an allergic reaction. Sometimes asthma results from inhaling dust or cigarette smoke causing difficult breathing and coughing. Asthma attacks sometimes recur and are difficult to predict. Mild asthma is treated medically at home but severe cases may require hospitalization and radiographs. Try to detect patterns of relationship between activities, exposures and attacks to avoid asthma triggering situations.