What is cough?
Coughing is a natural phenomenon that helps to clear phlegm from the respiratory system.
The cough can be acute and appear as a result of an infection. It can also be chronic if it lasts for several months. Coughing results in forced inspiration followed by violent expulsion of air from the lungs. One study found that air comes out of the lungs at around 250 m / s, a speed comparable to that of sound. This reflex action can evacuate any inhaled particles and bronchial secretions. It protects the airways.