The signs and symptoms of airborne allergies are familiar to many.
Sneezing, often with a runny or clogged nose
Coughing and postnasal drip
Itching eyes, nose, and throat
"Allergic shiners" (dark circles under the eyes
caused by increased blood flow near the sinuses)
"Allergic salute" (in a child, persistent upward
rubbing of the nose that causes a crease mark
on the nose)
In people who are not allergic, the mucus in the nasal
passages simply moves foreign particles to the throat,
where they are swallowed or coughed out. But something different happens in a person who is sensitive to
In sensitive people, as soon as the allergen lands on the
lining inside the nose, a chain reaction occurs that leads
the mast cells in these tissues to release histamine and
other chemicals. The powerful chemicals contract
certain cells that line some small blood vessels in the
nose. This allows fluids to escape, which causes the
nasal passages to swell—resulting in nasal congestion.
Histamine also can cause sneezing, itching, irritation,
and excess mucus production, which can result in
Other chemicals released by mast cells, including
cytokines and leukotrienes, also contribute to
Some people with allergies develop asthma, which
can be a very serious condition. The symptoms of
Shortness of breath
The shortness of breath is due to a narrowing of the
airways in the lungs and to excess mucus production
and inflammation. Asthma can be disabling and
sometimes fatal. If wheezing and shortness of
breath accompany allergy symptoms, it is a signal
that the airways also have become involved.
Courtesy: National Institute of Allergy and Infectious Diseases
|| San Antonio, Texas
Introduction to Allergies
What is an allergy?
What is allergic rhinitis? (Hay Fever)
Why are some people allergic?
What is an allergic reaction?
What Is Food Allergy?
Introduction to Asthma
What are Hives?