Chronic Cough
What is a chronic cough?
An occasional cough helps to protect your lungs by expelling unwanted material and this is normal. However, a chronic cough is one that persists for a number of weeks, and produces sputum or blood, disturbs your sleep, or affects school or work should prompt a referral to your GP or a lung specialist.
Causes of a chronic cough
There are a number of causes of chronic cough. Some of these include:
Postnasal drip. When your nose or sinuses produce extra mucus, it can drip down the back of your throat and trigger your cough reflex.
Asthma. An asthma-related cough may come and go with the seasons, appear after an upper respiratory tract infection, or become worse when you're exposed to cold air or certain chemicals or fragrances. In one type of asthma (cough-variant asthma), a cough is the main symptom.
Gastroesophageal reflux disease (GORD). This is a common condition where stomach acid flows back into the tube that connects your stomach and throat (oesophagus). The constant irritation can lead to chronic coughing. The coughing, in turn, worsens GORD — a vicious cycle.
Infections. A lingering cough post a viral or bacterial infection can occur.
Blood pressure drugs. Angiotensin-converting enzyme (ACE) inhibitors, which are commonly prescribed for high blood pressure and heart failure, are known to cause chronic cough in some people.
Chronic bronchitis. This is an inflammation of your major airways (bronchial tubes) can cause a cough that brings up colored sputum. Most people with chronic bronchitis are current or former smokers and may have other smoking related lung problems.
Other less common causes include:
Aspiration (food in adults; foreign bodies in children)
Bronchiectasis (damaged airways)
Bronchiolitis
Cystic fibrosis
Laryngopharyngeal reflux (stomach acid flows up into the throat)
Lung cancer
Nonasthmatic eosinophilic bronchitis (airway inflammation not caused by asthma)
Sarcoidosis (collections of inflammatory cells in different parts of your body, most commonly the lungs)
Risk factors for a chronic cough
Being a current or former smoker is one of the leading risk factors for chronic cough. Frequent exposure to secondhand smoke also can lead to coughing and lung damage. Women tend to have more-sensitive cough reflexes, so they're more likely to develop a chronic cough than are men.
When to see a doctor
See your doctor if you have a cough that lingers for weeks, especially one that brings up sputum or blood, disturbs your sleep, or affects school or work. Ask your GP for a referral to your local Respiratory Department for a consultation with a lung specialist
