What's an allergy?

An allergy is an immune reaction to a substance in the environment called an allergen.

When a child with allergies comes into contact with an allergen – either by touching it, breathing it, eating it, or having it injected – her body mistakenly views it as a dangerous invader and releases histamines and other chemicals to fight it off.
These chemicals irritate the body and cause symptoms such as a runny nose, sneezing, itching, and coughing. Symptoms can be mild or more severe, intermittent (seasonal, for example), or ongoing because of constant exposure to the allergen.

In some cases, an allergen can cause a severe reaction, called anaphylactic shock. This is a medical

emergency, as the symptoms – including difficulty breathing and swelling – can be life threatening

What are examples of allergens?

 Possible allergens include food, drugs, insects, animal dander, dust mites, mold, and pollen. Allergens can cause respiratory symptoms, as in nasal allergies or allergic rhinitis, skin symptoms like eczema, or intestinal problems – from food allergies for example.

What causes nasal allergies?

The most likely culprits are:

• Dust mites: microscopic organisms that thrive on human skin flakes. Nearly 85 percent of allergy sufferers are allergic to dust mites.
• Animal dander, those white, flaky specks made up of skin and hair shed by cats, dogs, and other furry animals.
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  Pollen, particularly from trees, grasses, and weeds.
• Mold: fungi found in wet, damp places such as bathrooms and basements or outdoors in humid climates.

Some children are allergic to down and feather pillows or wool blankets. And while most experts don't think children can be allergic to tobacco smoke, it can certainly make their allergic symptoms worse.

How can I tell if my child has nasal allergies or just a cold?

Because the symptoms of nasal allergies are much like cold symptoms – runny nose, watery eyes, cough, nasal congestion, sneezing – it can be tough to tell the difference. There are some telltale signs of allergies, though.
Ask yourself the following questions:

• Does it seem like your child always has a cold? Colds usually wind down in a week to ten days; allergies don't.
• Is your child's nose continually stuffy or running?
• Is she constantly wiggling, wiping, or pushing her nose up in what doctors call the allergic salute?
• Is the mucus that drains from her nose clear and thin (as opposed to yellow or greenish and thick)?
• Does she seem to sneeze a lot?
• Are her eyes itchy, red, and watery?
• Does the skin under her eyes look dark or purple or blue – what doctors call allergic shiners?
• Does she breathe through her mouth?
• Does she have a persistent dry cough?
• Is her skin irritated or broken out in an itchy red rash?