EVER WONDERED: Why you develop allergies

Monday, March 15, 2010; C10

Last month, I wrote about vaccines (shots). In case you need a quick refresher, vaccines stimulate your immune system to make antibodies against viruses or bacteria that can make you sick. These antibodies help your body attack the invading germs and neutralize them before they cause trouble.

It turns out that in addition to making antibodies to kill germs, the body's immune system sometimes messes up and makes antibodies to substances that are not dangerous -- such as plants. An example of this is hay fever, one of the most common disorders in the world. If you have hay fever, that means you are allergic to any one of a number of wind-pollinated plants including trees, grass and ragweed.

During allergy season, invisible grains of pollen swirl through the air like Dementors in search of their next victims. Eventually, some of this pollen will make its way into your nose and sinuses. If you are allergic to whatever is in the air, your body's misguided immune system will attack the pollen as though it were a ghoulish germ trying to make you sick. In the process of attacking the pollen, a chemical called histamine is released. Histamine causes watery, itchy eyes, sneezing, an itchy nose and sometimes even itchy skin.

Most people with hay fever suffer in spring (starting about now) when the trees are in bloom. Others have symptoms during summer (grass) or fall (ragweed). If you are allergic to dust, mold or house pets, you may have symptoms throughout the year.

People with dust allergies are really allergic to repulsive creatures known as dust mites. These microscopic bugs live in fabrics such as carpets, mattresses and stuffed animals. When dust mites die, their dried-up bodies mix with dirt and skin cells that fall off your body. These ingredients mix together to become house dust.

Most allergy medicines contain antihistamines that are designed to block the histamine released during the allergic process. Some allergy sufferers take nose sprays to reduce nasal inflammation. Here are some other tips that may help.

-- Keep your windows closed during allergy season.

-- If you are allergic to pets, keep the cute little beasts out of your bedroom.

-- Take a shower and change your clothes when you come in at night. This will not only get you clean -- and make your parents happy -- but it will also wash pollen off your body.

-- Howard Bennett

Howard Bennett, a Washington pediatrician and author of health-related books for kids, writes about gross things for KidsPost.

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