4. Bronchitis
The bronchioles are small tubes made of smooth muscle that diverge from the larger bronchi into each lung. Bronchitis is the inflammation of the bronchioles that normally occurs when a cold or respiratory infection afflicts the body. People with bronchitis normally experience coughing fits, chest discomfort, breathing difficulties, and production of phlegm along with mucus discoloration. Acute bronchitis is a common condition that normally lasts from seven to ten days. It is normally caused by viral infections, similar to those that cause influenza and colds.
Bronchitis is classified as chronic if coughing is observed for at least three weeks, along with recurring fits within the span of two years. It is highly probable for the symptoms to worsen if left untreated. Bronchitis is likely to develop in smokers because of their frequent exposure to chemicals and irritants. It can also develop as a result of other acute illnesses, such as influenza, or chronic conditions that weaken the immune system.