Coughs are necessary to expel foreign bodies and mucus
from the trachea and airways of the lungs.
Coughing
is a symptom rather than an illness, and can indicate
sinusitis, croup, bronchitis, pneumonia, flu, viruses,
the early stages of measles, asthma, whooping cough,
or an excess of catarrh from the nose or sinuses, due to
irritation or infection.
A dry cough may be caused by mucus from infections
or colds, chemicals in the atmosphere, a foreign object or
nervousness which constricts the throat.
A loose, wetter
cough is caused by inflammation of the bronchial tubes
produced by an infection or allergy. A constant nighttime
cough, or one which recurs with each cold and is hard to
get rid of, may indicate asthma.
Various terms describe the type of cough:
An acute cough starts suddenly, and is usually resolved
within a day or two.
A chronic cough persists, sometimes for many weeks.
A productive cough brings up lots of catarrh or mucus. A nonproductive cough brings up very little or no
mucus, and usually sounds harsh and hard.
