Asthma is a chronic inflammatory disease of the respiratory tract. Chronic: indicates that it is long-standing. Inflammatory: indicates the presence of swelling and increased mucus caused by inflammation of the airways. The greater the degree of this inflammation, the more difficult it is to breathe air in and out of the lungs. The inflammation referred to here is a “metabolic inflammation”, which is tissue damage caused by the body’s immune response; it is not the usual infection-induced inflammation that requires antibiotic treatment. When the swelling of the airways increases, the lining of the airways becomes very sensitive and the tiny muscles surrounding the airways begin to tighten. This is called “bronchospasm.” The inflammation may increase slowly over time, slowly and imperceptibly. If no anti-inflammatory measures are taken, it can lead to bronchial obstruction or contracture, and even life-threatening respiratory distress.