as one of the major disabling illnesses, allergies afflict more
than 40 million people in the in United States alone. As you know,
our immune system protects our body from all types of foreign
substances and dangerous microorganisms, called antigens, like
viruses, bacteria etc. It does this by producing a counter chemical
called an antibody, which fights these antigens. The antibodies
bind themselves to the antigens, which sets off a reaction. This
reaction between antibody and antigen ignites a series of events,
all designed to protect the body from infections.
immune system is programmed to ignore harmless substances like
food, pollen etc. However, sometimes it mistakes these innocuous
substances for harmful invaders and attacks them like it would
an antigen, by releasing powerful chemicals like histamines, to
destroy them. What happens is that when the body is exposed to
an allergen, it launches its counter offensive attack by releasing
an antibody called immunoglobulin E (IgE) through its mast cells.
The mast cells are a distinctive sets of cells of the immune system
located in areas where the body comes into contact with the outside
world , like the mucous membranes of the eyes and other areas,
and the linings of the respiratory and digestive systems. Their
function is to guard the body from outside influences. When IgE
encounters allergens, it triggers off the release of the chemical
histamine, from the mast cells. When the histamine binds it self
to the surrounding cells, through histamine receptors, the neighboring
cells become leaky, causing fluid collection, redness and swelling,
all of which are symptoms of an allergic reaction. Histamines
also trigger off pain receptors which cause itchiness in the eyes,
nose and throat, all symptoms of allergic rhinitis.
allergy then is a condition in which the body attacks harmless
substances like dust, pollen, food etc and releases antibodies
to subdue them. It is the release of histamines that produces
the disagreeable symptoms that are associated with allergies.
Allergic reactions are, most often, instantaneous, for e.g. one
may break out into a rash, or develop a sneezing fit. People who
are allergic to one substance will often find that they are sensitive
to a number of other substances.
offending agents, called allergens, range from dust, pollen, mold,
mildew, food, rubber, insect stings and even medicines. Common
food allergens include peanuts, fish, eggs and milk. An allergy
is one of the most common causes for asthma. An allergy can cause
the irritation, swelling and inflammation of the air passages,
which causes asthma.
estimate that over 20 percent of Americans suffer from some type
of allergy, making allergies a principal source of chronic disease
in the country.
About the Author
Rokwild writes about various topics.