When Is My Cough Considered "Chronic"?
Cough is a natural reflex that is meant to clear the airway of foreign material or irritants. The airway, which includes the larynx(voice box),pharynx(throat), trachea(windpipe), bronchi (large airways going to the lungs), bronchioles (small airways going to the lungs), and alveoli (lung tissue) can be affected at any site by many things that can cause cough. The nerve that sets off the cough reflex also innervates the esophagus so problems inside the esophagus can also cause cough.
Chronic cough is any cough that goes on for more than 6 weeks and should be evaluated by a physician. It is important to examine all areas of the airway and swallowing passages, either with endoscopes (small cameras) or with radiographs (x-rays). Infection is a common cause of cough and can be caused by viruses or bacteria. Irritation of the airways with smoking or by frequent exposure to fumes or particulates (like asbestos, wood dust, or construction dust) is a very common cause of cough. Nerve hyperirritability may cause cough long after an infection is cleared. Tumors in the chest, lung, throat, or esophagus can cause cough. Foreign bodies, often a cause of cough in small children, can become lodged in the airways causing cough.
Sinus drainage and allergies are a common cause of cough and chronic sinus infections may be responsible for a cough that goes on for greater than 6 weeks.