Asthma is a chronic condition impacting the air passages (bronchi) of the lungs, characterized by acute bronchoconstriction leading to airflow limitation and associated symptoms such as wheezing, coughing, and chest tightness. The airways of individuals with asthma are inflamed, rendering them hypersensitive to various triggers that can induce bronchoconstriction and provoke asthma symptoms.
During inhalation, air travels through the nose for warming, filtering, and humidifying before passing into the windpipe (trachea), then dividing into two large tubes known as the right and left bronchi. Further division of these bronchi forms smaller tubes within the lungs called bronchioles. Both small and large bronchi are typically affected in asthma.
In individuals with asthma, exposure to irritants or trigger factors causes constriction and increased inflammation of the small airways in the lungs. This constriction and swelling make breathing challenging. Notably, asthma is a persistent condition, with lung inflammation persisting even during symptom-free periods. Asthma symptoms can occur unpredictably in individuals with inflamed airways or when exposed to triggers.
Asthma can be categorised as Allergic asthma and Non-allergic asthma
- Allergic asthma: This type of asthma is more common in children and adolescents. Allergic asthma can develop even in adults. An acute asthma attack occurs when the person comes into contact with something to which he is allergic.
- Non-allergic asthma: This type of asthma is more common in middle-aged adults and the trigger factors for this type of asthma are exercise, cold air, and respiratory infections.