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What you need to know about

Chronic cough

What is chronic cough?

  • Defined as coughing that lasts eight weeks or longer in adults and four weeks in children
  • Can ruin sleep and leave you feeling exhausted
  • Severe cases can result in vomiting, lightheadedness, headaches, urinary incontinence, excessive sweating, depression and even rib fractures
  • May be referred after initial consultation with family physician to an allergist, who specializes in treating chronic cough

Signs and symptoms

  • Runny or stuffy nose
  • Feeling of liquid running down back of throat
  • Frequent throat clearing, sore throat
  • Hoarseness
  • Wheezing, shortness of breath
  • Heartburn or sour taste in mouth
  • Coughing up blood (in rare cases)


Studies show the following factors and causes, alone or in combination, are responsible for 90% of chronic cough cases:

  • Postnasal drip or upper airway cough syndrome – When extra mucus that drips down back of throat triggers cough reflex.
  • Asthma – Asthma-related cough may come and go with the seasons, appear after an upper respiratory tract infection or become worse in cold air or with exposure to certain chemicals or fragrances. In cough-variant asthma, cough is main symptom.
  • Gastroesophageal reflux disease (GERD) – Common condition in which stomach acid flows back into tube connecting stomach and throat (esophagus). A vicious cycle ensues, with constant irritation leading to chronic coughing, which then worsens GERD.
  • Tobacco smoke

Other common causes

  • Blood pressure drugs such as angiotensin-converting enzyme (ACE) inhibitors, commonly prescribed for high blood pressure and heart failure
  • Infections – Cough can linger long after most symptoms of a cold, influenza, pneumonia or other upper respiratory infections have gone away. Chronic cough in adults is often caused by pertussis, also known as whooping cough.
  • Chronic bronchitis – Long-standing inflammation of major airways (bronchial tubes) can cause congestion, breathlessness, wheezing and cough that brings up discolored sputum. Most people with chronic bronchitis are current or former smokers.

Less common causes

  • Aspiration
  • Bronchiectasis
  • Bronchiolitis
  • Chronic bronchitis from infectious disease
  • COPD
  • Cystic fibrosis
  • Foreign body aspiration (children)
  • Laryngopharyngeal reflux
  • Lung cancer
  • Non-asthmatic eosinophilic bronchitis
  • Sarcoidosis