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What is a Cough?

A cough is a reflex action that is caused by the stimulation of an irritated airway. When a person coughs, the larynx closes briefly. The chest and abdominal muscles then contract and air is forced out of the lungs when the larynx is reopened. The air released by a cough cleans out the airway of any irritants.

Coughing is a key part of the body's defence mechanism as it purges the respiratory passages of dirt, dust or fluid which could cause problems to the lungs.

Causes of coughing

The causes of coughs can be described depending on how long the cough has been around for.

Most people with coughs experience an acute cough as a result of a respiratory tract infection (by viruses or bacteria) such as the common cold, flu, laryngitis or bronchitis. Acute coughing may be seen as a dry cough or a chesty cough.

A chronic cough in adults is most commonly due to smoking, asthma or as a result of prescribed medication. Again, these coughs could be both dry or chesty.

Where children are concerned, a persistent cough may indicate a more serious condition such asthma or whooping cough.

In any case, if unexplained coughing persists for more than three weeks in either children or adults, your GP must be consulted. In smokers, there is always the possibility that a cough could be a sign of lung cancer but remember that non-smokers may also, in rare circumstances, develop this condition.

Types of coughs

Coughs may be described as:

  • A dry cough
  • A chesty cough

A dry cough develops because of infection or inflammation of the throat and upper airway. As no fluid is produced, it is said to be non-productive or dry. The most common cause of a dry cough is the common cold or flu - the brain recognises the inflammation in the throat as a foreign object and tries to remove it through coughing.

A chesty cough brings up mucus produced from the airways, also known as phlegm. This fluid is produced because of infection or inflammation lower in the airways or because of the presence of bacteria. Chesty coughs can produce phlegm which is clear or white – or if green, indicates the presence of bacteria.

Cough remedies

There are many different remedies on offer to help clear up a cough.

  • One of the simplest cures is a homemade remedy containing honey and lemon. Honey coats the throat and relieves the irritation which causes coughing.
  • Herbal remedies used to relieve coughs include Ivy, Thyme and Pine Shoots.
  • There are people who prefer to use chemical medicines to suppress coughs – these are readily available from pharmacies and retail outlets.
  • If a cough is persistent, your GP should be consulted as prescribed medication may be needed.

In all cases, remember that a cough is not a disease, it is a symptom. Therefore to clear up a cough permanently, the underlying cause of coughing (most often a viral or bacterial infection) must be treated.

Preventing a cough

As there are so many causes for coughing, prevention of coughs lie with looking at the underlying problem.

Nevertheless, lifestyle choices such as smoking can greatly increase the chances of getting a cough. It has been shown that giving up cigarettes will lessen or even abolish a smoker's cough by 94% within four weeks.

In addition, obesity, anorexia and an unhealthy diet with too little exercise will increase the likelihood of developing asthma or other respiratory problems which will cause a cough to develop.