Know More about Causes of Cough

Know More about Causes of Cough

            Cough is produced by inflammatory, mechanical, chemical and thermal stimulation of cough receptors. Following are the causes of cough :

1.      Inflamatory process in trachea, laryng, bronchi, bronchioli and tissue of the lung

2.      Mechanical process --- inhalation of particulates such as dust, foreign bodies or compression of airways ( malignancy process).

3.      Chemical ---inhalation of irritant fumes including cigarette smoke

4.      Thermal, inhalation of cold or very hot air.

Diagnosis the causes of cough may be associated with the illness history of  the patient. An approach seems to be an important way to get that. A good physician may concern about duration of cough, presence of fever or wheezing, sputum quantity and character, seasonal or temporal pattern, risk factors for underlying disease such as environmental exposure that suggest occupational asthma, past medical history, drugs such as ACE Inhibitor drug group for hypertension therapy that will causes chronic cough in 5-20 % patient.

Short duration with associated fever suggests acute viral or bacterial infection. Persistent cough after viral illness suggests postinflamatory cough and postnasal drip is common cause of chronic cough. The nocturnal cough may indicate chronic sinus drainage or esophageal reflux.

A good physical examination should assess upper and lower airways and lung parenchyma. A stridor sound of the lung suggests upper airway obstruction, wheezing suggests bronchospasm, midinspiratory crackles indicate airways disease e.g. chronic bronchitis and fine end inspiratory crackles occur in interstitial fibrosis and heart failure.

A Chest X-ray may show us a possibility of lung cancer, infection and interstitial disease. A High resolution Computed Tomography helpful in unexplained chronic cough. A Sputum examination can indicate a malignancy process or infection like tuberculosis.

Therapy of cough is that of underlying disease, eliminate ACE inhibitor and smoking cessation. If no cause can be found, a trial of an inhaled anticholinergic agent e.g ipratropium, an inhaled steroid, an inhaled albuterol can be attempted. Inhaled steroid may take 7-10 days to be effective when used for an irritative cough. Cough productive of significant volumes of sputum should generally not be suppressed. Sputum clearance can be facilitated with adequate hydration, expectorants and mechanical devices. Iodinated glycerol may be useful in asthma or chronic bronchitis.

When symptoms from an irritative cough are severe, the cough may be suppressed with a narcotic antitussive agent such as codeine or a nonnarcotic such as dextromethorphan.