You've had the feeling before - you come home from school
feeling awful with a sore throat. Your mom feels your head with her
hand, frowns, and takes your temperature with a thermometer. Within
a few minutes, you hear the word
But what are fevers, exactly? Why do kids get them? Why do
parents and doctors care so much about them? And once you have one,
how do you get rid of it? Don't go back under the covers just
yet - read on to learn more about the facts on fever.
It All Begins in Your Brain
To really understand what a fever is, you need to say hello to
-luh-mus). The hypothalamus is in the center of your
. Think of it as your body's thermostat - like that thing
on the wall in your house that you use to set the heat or the air
conditioning. Your hypothalamus knows what temperature your body
should be and will send messages to your body to keep it that
Most human beings have a body temperature of around 98.6Âº
Fahrenheit (37Âº Celsius). Some people will have a normal
temperature that's a little higher; others will have a normal
temperature that's a little lower.
Most people's body temperatures even change a little bit
during the course of the day: It is usually a little lower in the
morning and a little higher in the evening. For most kids, their
body temperature stays pretty much the same from day to day - until
germs enter the picture.
The Germs March In
that made you feel so rotten? Or another time when
made you feel tired and achy? These kinds of infections are caused
by germs that make their way into your body, usually in the form of
bacteria (say: bak-
-ee-uh) or viruses.
march in and make you sick, they can sometimes cause certain
chemicals to flow into your blood. When your hypothalamus gets word
that these chemicals are on the scene, it automatically sets your
body's thermostat higher. Instead of saying your body should be
98.6Âº Fahrenheit (37Âº Celsius), your body's thermostat might
say that it should be 102Âº Fahrenheit (38.9Âº Celsius).
Why does the hypothalamus tell your body to change to a new
temperature? Researchers believe turning up the heat is the
body's way of fighting the germs and making your body a less
comfortable place for them. A fever is also a good signal to you,
your parents, and your
that you are sick. Without fever, it would be much more difficult
to tell if a person had an infection and how severe it was.
That's why grown-ups are concerned when you have a fever.
Shiver, Then Sweat
Once your hypothalamus sets a new temperature for your body,
your body takes action and starts to heat up. When a fever
starts, your body tries to get hotter and you may shiver without
thinking about it to create more heat. You may feel very cold even
though the room isn't cold and even though you have your
pajamas or nightgown on and lots of blankets around you.
If your body reaches the new temperature that's been set by
the hypothalamus - say 102Âº Fahrenheit (38.9Âº Celsius) - you
won't feel cold anymore. According to your hypothalamus, your
temperature is where it should be!
After the cause of the fever disappears, your hypothalamus will
set everything back to a normal temperature. When your strep throat
medicine starts to work, for instance, your body will begin to cool
down and you'll no longer have the chills. You'll begin to
feel warm and will need to get rid of the extra heat that's
been in your body. You may sweat and decide to change into some
Fighting a Fever
For almost all kids, fevers aren't a big problem. Once the
cause of the fever is treated or goes away on its own, your body
temperature comes back down to normal and you feel like your old
self again. Most doctors say that kids with a fever less than 102Âº
Fahrenheit (38.9Âº Celsius) don't need to take any special
medication unless their fevers are making them uncomfortable.
It's a different story for newborns and very young infants,
though. They should be evaluated by a doctor for any fever that
reaches 100.4Âº Fahrenheit (38Âº Celsius) or higher.
If a kid has a higher fever, the doctor usually will tell a
parent to give the child medicine. The two
most often recommended are
-fen). The medicine blocks the chemicals that tell the hypothalamus
to turn up the heat. Kids should
take aspirin to treat a fever because it can cause a rare but
If you have a fever, your mom or dad will probably ask you to
drink fluids. That's important because as your body heats up,
it's easy for it to get
-drayt-ed), which means there isn't enough water in your body.
You have a lot of choices when it comes to fluids - juice, water,
sports drinks, soup, flavored gelatin, and even ice pops. Before
you know it, your mom or dad will pull the thermometer out of your
mouth and say, "Your temperature is normal. No more
Mary L. Gavin, MD
Date reviewed: April 2007
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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