Asthma is a chronic lung disease that inflames and narrows the airways. Asthma causes recurring periods of wheezing, chest tightness, shortness of breath and coughing. The coughing often occurs at night or early in the morning. They tend to react strongly to certain substances that are breathed in. As a result muscles around them tighten. This causes the airways to narrow, and less air flows to lungs. The swelling also can worsen, making the airways even narrower. Cells in the airways may make more mucus than normal. Mucus is a sticky, thick liquid that can further narrow airways.About 12 percent of children (< 18 years) and 8 percent of pregnant women have asthma.

Types:

• Allergic Asthma

• Intrinsic Asthma

• Exercise-Induced Asthma

• Nocturnal Asthma

• Occupational Asthma

• Steroid-Resistant Asthma