Excessive Production of Sputum
Gradually, the air passages get narrower by accumulation of irritants forming debris resulting in more irritation. In response to this process, there is secretion of copious mucus which causes the characteristic cough of bronchitis. Cough in bronchitis is productive, which means there will be sputum production, and the patient will either spit mucus or hear it moving in the airways as they cough.
The sputum in bronchitis can be clear or white, or may also be yellowish, green or blood filled when the disease is not managed in time, and in cases of chronic bronchitis. Another difference between acute and chronic bronchitis is that sputum in chronic bronchitis is usually excessive, while acute bronchitis has less amount of sputum unless complicated or in severe cases.