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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.

What are the Causes of Chronic Cough?

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.

What Tests Can Be Done to Determine the Cause of Chronic Cough?

Your doctor may decide to perform one or more of the following tests to evaluate the cough:

  • Lung imaging such as a chest X-ray or computed tomography (CT) scan
  • Lung function testing
  • Sputum tests to check for bacteria that may be causing an infection

How is Chronic Cough Treated?

Treatment of chronic cough depends on the underlying cause of the cough.

For example:

  • Post-nasal drip may be treated with nasal sprays
  • Asthma may be treated with inhalers
  • Acid reflux may be treated with medications to reduce the acidity of stomach contents

In addition, your doctor may prescribe medications to suppress the cough.

What Should I Look Out for?

It is important that you contact your doctor if:

  • You cough up blood
  • You have chest pain or trouble breathing when you cough
  • You have unexplained weight loss
  • Your cough is getting worse or if there is a change in the pattern of your cough

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