Asthma

Asthma is a chronic inflammation of the lungs in which the airways (bronchi) are reversibly narrowed. Asthma affects 7% of the population, and 300 million worldwide. During attacks (exacerbations), the smooth muscle cells in the bronchi constrict, and the airways become inflamed and swollen. Breathing becomes difficult, and asthma causes 4,000 deaths a year in … Asthma