What is Cough?

A cough is:

• The sound made when air is forcefully passed through the voice box.
• The body's way of clearing particles or secretions from the respiratory tract.
• Not a disease but may be a common symptom of different upper and lower respiratory tract diseases.

How is Cough Classified?

There are 3 time periods used to describe how long someone has had cough:

• Acute (lasts less than 3 weeks)
• Subacute (lasts 3 to 8 weeks)
• Chronic (lasts more than 8 weeks)

Patients who are referred to the Respiratory Medicine clinic usually have chronic cough that has not improved despite treatment by a primary care physician like General Practitioners (GPs) or Polyclinic doctors.

Common causes of chronic cough are:

• Post-nasal drip – where mucus runs down the back of your nose to your throat.
• Asthma.
• Acid reflux – where some of the acidic stomach contents go back up into the esophagus (also known as the food pipe).

Other causes of chronic cough include:

• Medications
• Smoking and smoking-related lung disease
• Respiratory tract infections
• Cancer
• Interstitial lung disease where there is scarring of the lungs

However, some patients may experience chronic cough with unclear causes despite extensive evaluation.