What Are Allergies?
Your eyes itch, your nose is running, you're sneezing, and
you're covered in hives. It's allergy season again, and all
you want to do is curl up into a ball of misery.
There has to be something you can do to feel better. After all,
doctors seem to have a cure for everything, right? Not for
allergies. But there are ways to relieve allergy symptoms or avoid
getting the symptoms, even though you can't actually get rid of
the allergies themselves.
Allergies are abnormal immune system reactions to things that
are typically harmless to most people. When you're allergic to
something, your immune system mistakenly believes that this
substance is harmful to your body. (Substances that cause allergic
reactions, such as certain foods, dust, plant pollen, or medicines,
are known as
.) In an attempt to protect the body, the immune system produces
to that allergen. Those antibodies then cause certain cells in the
body to release chemicals into the bloodstream, one of which is
The histamine then acts on a person's eyes, nose, throat,
lungs, skin, or gastrointestinal tract and causes the symptoms of
the allergic reaction. Future exposure to that same allergen will
trigger this antibody response again. This means that every time
you come into contact with that allergen, you'll have an
Allergic reactions can be mild, like a runny nose, or they can
be severe, like difficulty breathing. An
attack, for example, is often an allergic reaction to something
that is breathed into the lungs in a person who is susceptible.
Some types of allergies produce multiple symptoms, and in rare
cases, an allergic reaction can become very severe - this severe
reaction is called
-sis). Some of the signs of anaphylaxis are difficulty breathing,
difficulty swallowing, swelling of the lips, tongue, and throat or
other parts of the body, and dizziness or loss of consciousness.
Anaphylaxis usually occurs minutes after exposure to a triggering
substance, such as a peanut, but some reactions may be delayed by
as long as 4 hours. Luckily, anaphylactic reactions don't occur
often, and they can be treated successfully if proper medical
procedures are followed.
Why Do People Get Allergies?
The tendency to develop allergies is often hereditary, which
means it can be passed down through your genes. (Thanks a lot, Mom
and Dad!) However, just because a parent or sibling might have
allergies, that doesn't mean you will definitely get them, too.
A person usually doesn't inherit a particular allergy, just the
likelihood of having allergies.
What Are Some Things That People Are Allergic To?
Some of the most common allergens are:
are most common in infants and often go away as a child gets older.
Although some food allergies can be serious, many simply cause
annoying symptoms like an itchy rash, a stuffy nose, and
. Most allergy specialists agree that the foods that people are
most commonly allergic to are milk and other dairy products, eggs,
wheat, soy, peanuts and tree nuts, and seafood.
Insect bites and stings.
The venom (poison) in insect bites and stings causes allergic
reactions in many people. These allergies can be severe and may
cause an anaphylactic reaction in some people.
These are often called environmental allergens, and they're the
most common allergens. Some examples of airborne particles that can
cause allergies in people are dust mites (tiny bugs that live in
house dust); mold spores; animal dander (flakes of scaly, dried
skin, and dried saliva from your pets); and pollen from grass,
ragweed, and trees.
Antibiotics - medications used to treat infections - are the most
common types of medicines that cause allergic reactions. Many other
medicines, including over-the-counter medications (those you can
buy without a prescription), can also cause allergic reactions.
Some cosmetics or laundry detergents can cause people to break out
in an itchy rash (hives). Usually, this is because the person has a
reaction to the chemicals in these products. Dyes, household
cleaners, and pesticides used on lawns or plants can also cause
allergic reactions in some people.
How Do Doctors Diagnose and Treat Allergies?
If your family doctor suspects you might have an allergy, he or
she might refer you to an allergist, a person who specializes in
allergy treatment, for further testing. The allergy specialist will
ask you questions both about your own allergy symptoms (such as how
often they occur and when) and about whether any family members
have allergies. The allergist will also perform tests to confirm an
allergy - these will depend on the type of allergy a person has and
may include a skin test or blood test.
The most complete way to avoid allergic reactions is to stay
away from the substances that cause them (called
). Doctors can also treat some allergies using medications and
In some cases, like food allergies, avoiding the allergen is a
life-saving necessity. That's because, unlike allergies to
airborne particles that can be treated with shots or medications,
the only way to treat food allergies is to avoid the allergen
entirely. For example, people who are allergic to peanuts should
avoid not only peanuts, but also any food that might contain even
tiny traces of them.
Avoidance can help protect people against non-food or chemical
allergens, too. In fact, for some people, eliminating exposure to
an allergen is enough to prevent allergy symptoms and they
don't need to take medicines or go through other allergy
Here are some things that can help you avoid airborne
- Keep family pets out of certain rooms, like your bedroom, and
bathe them if necessary.
- Remove carpets or rugs from your room (hard floor surfaces
don't collect dust as much as carpets do).
- Don't hang heavy drapes, and get rid of other items that
allow dust to accumulate.
- Clean frequently (if your allergy is severe, you may be able
to get someone else to do your dirty work!)
- Use special covers to seal pillows and mattresses if
you're allergic to dust mites.
- If you're allergic to pollen, keep windows closed when
pollen season's at its peak, change your clothing after being
outdoors - and don't mow lawns.
- Avoid damp areas, such as basements, if you're allergic
to mold, and keep bathrooms and other mold-prone areas clean and
Medications such as pills or nasal sprays are often used to
treat allergies. Although medications can control the allergy
symptoms (such as sneezing, headaches, or a stuffy nose), they are
not a cure and can't make the tendency to have allergic
reactions go away. Many effective medications are available to
treat common allergies, and your doctor can help you to identify
those that work for you.
Another type of medication that some severely allergic people
will need to have on hand is a shot of
-frin), a fast-acting medicine that can help offset an anaphylactic
reaction. This medicine comes in an easy-to-carry container that
looks like a pen. Epinephrine is available by prescription only. If
you have a severe allergy and your doctor thinks you should carry
it, he or she will give you instructions on how to use it.
Allergy shots are also referred to as
. By receiving injections of small amounts of an allergen, your
body can gradually develop antibodies and undergo other immune
system changes. These changes help block the reaction caused by the
substance to which you're allergic.
Immunotherapy is only recommended for specific allergies, such
as allergies to things you might breathe in (like pollen
or pet dander) or insect allergies.
Immunotherapy doesn't help with some allergies, like food
Although a lot of people find the thought of allergy shots
unsettling, shots can be highly effective - and it doesn't take
long to get used to them. In many cases, the longer a person
receives allergy shots, the more they help the body build up
antibodies that fight the allergies. Although the shots don't
cure allergies, they do tend to raise a person's tolerance when
exposed to the allergen, which means fewer or less severe
If you're severely allergic to bites and stings, talk to a
doctor about getting venom immunotherapy (shots) from an
Is It a Cold or Allergies?
If the spring and summer seasons leave you sneezing and
wheezing, you may suffer from allergies. Colds, on the other hand,
are more likely to occur at any time (though they're more
common in the colder months). Although colds and allergies produce
similar symptoms, colds usually last only a week or so. And
although both may cause your nose and eyes to itch, colds and other
viral infections may also give you a fever, aches and pains, and
colored mucus. Cold symptoms often worsen as the days go on and
then gradually improve, but allergies begin immediately after
exposure to the offending allergen and last as long as that
exposure continues. If you're not sure whether your symptoms
are being caused by allergies or a cold, talk with your doctor.
Dealing With Allergies
So once you know you have allergies, how do you deal with them?
First and foremost, try to avoid things you're allergic to! If
you have a food allergy, that means avoiding foods that trigger
symptoms and learning how to read
to make sure you're not consuming even tiny amounts of
allergens. For people with environmental allergies, keeping your
house clean of dust and pet dander and watching the weather for
those days when pollen is high can help. Switch to perfume-free and
dye-free detergents, cosmetics, and beauty products (you may see
non-allergenic ingredients listed as
on product labels).
If you're taking medication, be sure to follow the
directions carefully and make sure your regular doctor is aware of
anything an allergist gives you (like shots or prescriptions). If
you have a severe allergy, you may want to consider wearing a
medical emergency ID (such as a MedicAlert bracelet), which will
explain your allergy and who to contact in case of an
If you've been diagnosed with allergies, you have a lot of
company. The National Institutes of Health (NIH) report that more
than 50 million Americans are affected by allergic diseases. The
good news is that doctors and scientists are working to better
understand allergies, to improve treatment methods, and to possibly
prevent allergies altogether.
William J. Geimeier, MD
Date reviewed: May 2007
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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