YESTERDAY, when I took off
my watch, I noticed a patch
of peeling, red skin around
where the strap had been. I went
to my family doctor who told me I
had an allergy to the metal parts
of my watch. What does allergy
mean? Is it something like an
An allergy is not an infection. It
manifests because of your own
body's immune response.
All our bodies are primed to
defend against foreign substances
invading it, such as bacteria, viruses
etc. This is a natural protective
Sometimes, we have an exaggerated immune response when our body is in contact
with certain foreign substances. These substances
cause most people no harm, but our
bodies sometimes see it as harmful.
Thus, we are "allergic" or "atopic" to
that particular substance.
These foreign substances that
produce allergies in allergic people
are called "allergens".
The word allergy was coined in
1905 by an Austrian paediatrician
named Clemens Pirquet. It is
derived from the Greek words
"allos", meaning different or
changed, and "ergos", meaning
work or action. Thus allergy roughly
means "altered reaction".
But I thought allergies were only
confined to people with asthma?
No. There are many types of "allergic" diseases, including asthma and
allergic rhinitis, and all come under
the broad spectrum of allergy.
How does allergy manifest? Is it
only itching? Or does it involve
The parts of the body that are prone
to react to allergies are the nose,
skin, eyes, lungs, and stomach.
For example, in allergic rhinitis
(commonly known as "hay fever"),
you have runny nose, blocked or
stuffy nose, sneezing, itching, and
sometimes a lot of throat clearing
because the liquid drips from
behind your nose into your throat.
Allergic rhinitis is the most common of the allergic diseases. Some
people have it seasonally, especially
during spring, where a lot of pollen
is released. Some people have it all
through the year, and this is usually
caused by indoor allergens such as
dust mites, animal dander, or
Asthma is another very common
allergic disease. Here, there is shortness of breath, wheezing and chest
tightness caused by the inflammation and spasm (narrowing) of the
lung's air passages (bronchial airways). A lot of people also have
The eye is another commonplace
for allergies. Allergic conjunctivitis
is the inflammation of the conjunctiva, which causes redness, watery
and itchy eyes and swelling.
In the skin, it manifests itself as
"hives" (called urticaria). These are
intensely itchy swellings that can
occur on any part of your body.
Allergic reactions can also manifest as allergic eczema (atopic dermatitis).
There is redness, itching, and dryness of the skin. This is common in children.
Do people die from allergies? I remember seeing this TV program about a man who ate a
peanut. He started to swell. He
was dead within minutes.
This sounds a bit drastic, but yes,
people have been known to die
from allergies. Allergic shock (anaphylactic shock) sends the body
.into massive immune response
overload, causing the tissues and
organs to swell and the blood pressure to drop dramatically because
the blood vessels turn leaky. This is
usually in response to a food being
eaten or a sting (for example, a bee
or scorpion sting).
How will I know if I'm allergic to
something? It would be very difficult to pinpoint the source.
You are right. It can be very difficult. You have to go back to the patterns of your behaviour, or whether
there has been a new addition to
For example, you were never
allergic to anything before.
Suddenly, a new dog arrives. Then
you begin to sneeze violently and
have watery eyes. But your wife
and children have no reaction.
Solution: you are very likely allergic to the dog's hair (animal dander)!
Apparently, there was a period of
"sensitisation" to the dog hair that had occurred in you in the past that you
weren't aware of. It may range from months to years. You have previously been in prior contact with
dog hair and your body began to
develop an immune reaction to it.
So when the new dog came into
your house -- wham! Allergic reaction.
The most common things people are allergic to are pollen from grass, trees,
weeds, dust mites (manifest- ed when you are doing house cleaning!), animal proteins (fur, hair,
urine, cockroach parts), spores from
moulds, shellfish, cow's milk, certain medicines, peanuts, sesame oil,
latex (as in gloves, condoms), certain plants (poison ivy), nickel (as in
watches, jewellery), certain cosmetics, certain dyes used in fabric
colouring etc, insect venom.
You should avoid the allergen
and there are drugs such as antihistamines to suppress the inflammatory response.