hypersensitive condition characterised by breathing
difficulties caused by a narrowing of the air passage
leading to the lungs.
The main symptoms are
breathlessness and a wheezing cough that may worsen at
night or early in the morning. In severe attacks, the
breathing rate increases considerably and is rapid and
shallow. It is caused by swelling and inflammation of
the walls of the air passage, and contraction of the
muscles, whereby openings are narrowed. Usually it is
triggered by a number of different allergens.