health

Asthma is a condition that causes episodic breathing difficulties. These
episodes are caused by narrowed and inflamed airways of the lungs.
Asthma “flares” or “attacks” can be triggered by dust, pollutants, smoke,
allergies, cold air, or infections.

Several changes happen inside the airways in the lungs of people who
have asthma. First, there is inflammation, or swelling, of the lining of
the airways. Second, the swollen tissues make a thick, slippery substance
called mucus*. Third, the muscles around the airways may squeeze tight,
causing the airways to narrow. These three processes—inflammation,
mucus production, and muscle constriction—combine to reduce the size
(the diameter) of the airways. That makes it harder to breathe, like trying
to blow air through a narrow straw.
During an asthma attack, these changes get worse. The airways swell
on the inside while they are being squeezed on the outside. At the same
time, thick mucus plugs the smaller airways. The person may start to
make whistling or hissing sounds with each breath. The person’s chest
may also feel tight. In addition, the person may cough to try to clear the
lungs.


A Breathless Story