How do cough and sneeze reflexes remove irritants from the body?

The cough and sneeze are automatic, inborn reflex actions that serve as vital defense mechanisms to protect the body from irritants. These responses are controlled by the medulla oblongata and function as follows:1

• Stimulus: The cough reflex is triggered by irritants in the trachea, while the sneeze reflex is initiated by irritants in the nose.1
• Mechanism: Both reflexes involve a coordinated response from many muscles, including a temporary pause in normal breathing. This action results in a sudden, forceful expulsion of air from the lungs, which carries away foreign material, noxious fumes, or excessive secretions from the respiratory tract.12

These reflexes are essential for maintaining respiratory health; when the cough reflex is impaired due to injury or disease, individuals are at a significantly higher risk for conditions such as pneumonia. While these responses are stereotyped, they can be influenced by higher levels of the nervous system, allowing the cough reflex to be suppressed voluntarily.21