Allergies in Children

Sometimes, the sniffles are more than you bargained for. See staying healthy pictures to learn more.

Any parent can attest to the fact that there's no shortage of things to worry about when it comes to raising children. When one of those worries becomes a reality in the form of a medical condition, "normal" worries begin to seem like the good old days.

Allergies are one such condition, ranging from nuisance to red alert in terms of severity. After coming in contact with an allergen (a cat, for instance), a kid with allergies might exhibit itchy, watery eyes and red, splotchy skin. A runny nose is another common symptom, and sometimes, children will rub their noses so often that the upward motion of the hand causes a crease to appear on the bridge of their nose. That's not the only cosmetic effect -- some children suffering from allergies develop what appear to be black eyes (as if they've been struck on the face) that develop as a result of nasal congestion. Stuffy noses can also lead to labored breathing through the mouth.


These symptoms may seem minor, but they add up. When allergies are in effect, kids can lose sleep, spending their days tired and irritated as a result. Frequent loss of sleep means missed school days and a drop in academic performance. And when a kid has to stay home from school, it often means a parent has to take a day off work, too.

Sometimes it's easy to pinpoint what's causing your child's allergic reaction. Perhaps you just brought home a new puppy, or your child just ate a certain food. But sometimes, finding the culprit is quite difficult.

So what exactly are allergies? How common are they? Are some children "more allergic" than others? And what can set off an allergic reaction anyway?

Let's begin by taking a look at what happens inside the body when an allergic reaction occurs.


Your immune system protects you against all kinds of antigens -- unwanted, invasive agents like viruses, bacteria and other harmful substances. When an antigen is detected, the immune system sends out immunoglobulins (you may know them as antibodies) to get rid of the intruder.

There are four different types of immunoglobulin that your body can produce in response to the presence of a harmful substance: G, M, A or D. These immunoglobulins attach to other immune cells called mast cells. When this mast cell/immunoglobulin hybrid locates the antigen, it sticks to it. Now, the immune system has the antigen right where it wants it. The mast cell then releases histamines and other chemicals to destroy the immobilized antigen.

Like all great complicated systems, sometimes the immune system gets a bit wonky. It's possible for a perfectly harmless substance to be mistaken for a harmful agent, triggering an abnormal response in the immune system. This is an allergic reaction. The substance could be dust, cat hair, pollen, peanuts or any number of things. But when your immune system detects it, it promptly freaks out and releases a fifth kind of immunoglobulin: E, also known as IgE (immunoglobulin E). People who have no allergies don't have IgE released into their bodies. It's the presence of IgE that determines whether or not an allergic reaction is taking place.

We've already mentioned common allergic symptoms like skin rash, runny nose and watery eyes, but it can get much worse than that. Some people have allergic reactions that result in anaphylaxis, which is something like a nuclear allergic meltdown that can be life-threatening. Anaphylaxis can cause severe reactions to many parts of the body at once, including the throat, lungs and skin.

Fortunately, anaphylaxis can be treated with epinephrine (adrenaline) which helps end the state of shock by boosting blood pressure and opening up the airways in the lungs. Epinephrine can be administered (or self-administered) via injection into the thigh with a small, penlike device that many allergic children and their parents carry with them at all times.

Now that we know how allergic reactions happen, let's find out how you diagnose an allergy.

A patch test looks a little something like this.
A patch test looks a little something like this.

Sometimes children's allergies are all too apparent, and sometimes they're not. If you suspect your child has allergies, you should have them checked out by your family doctor. Breaking out in hives may be the result of any number of things, and medical advice and testing are a good idea when you're dealing with any kind of adverse reaction.

Among kids under age 6, allergies are an issue for about 8 percent of them [source: Asthma and Allergy Foundation of America]. Children who have allergies often have asthma, too -- about four out of five kids with asthma have allergies [source: Asthma and Allergy Foundation of America].

If you think your kid is allergic to something (or many things), your pediatrician will likely recommend an allergist who will collect anecdotal accounts from you, thoroughly examine the child, and test him or her for indications of allergic reaction (chiefly the presence of IgE).

The allergist may check for allergies through a number of different methods. One is an elimination test, for which different foods and possible allergens are removed from the child's environment until symptoms disappear. One by one, the substances are reintroduced into the child's life until one triggers a reaction.

A skin-prick test may be performed, in which skin on the back or arm is pricked with one or more needles that contain traces of specific allergens. The allergist then looks for a raised bump on the site of injection, and the bump's size indicates the degree of allergic reaction. Results aren't always reliable, though, and may produce a false positive or a false negative.

Another allergy test is the RAST test (radioallergosorbent test), during which radioactive markers are introduced to the child's body to check for an IgE reaction. Many other tests are available (such as patch testing), but they're less widely used. Your allergist will help you choose the best for your child's situation. The good news is that by testing different allergens, the allergist may discover more than one that triggers an allergic reaction. That doesn't sound like good news, but if your child has multiple allergies, it's best to discover them in a medical facility and not when you least expect it.

Next, we'll learn about food allergies in particular.

In 2007, about 3 million American kids were reported to have a food allergy, but the number of kids with proven food allergies is actually closer to 2.1 million (the difference in numbers resulting chiefly from parental misdiagnosis) [source: National Center for Health Statistics, Stoppler]. While a lot of kids have allergies, they're usually not too serious; with that 2 million or so kids with allergies, there were fewer than 10,000 emergency-room visits for kids due to food allergies in 2006 [source: NCHS Press Room].

As far as parental misdiagnosis goes, often, food intolerance is mistaken for food allergy. It's an easy mistake to make, since both food intolerance and food allergy often share the same features. For instance, the symptoms of lactose intolerance and milk allergy, two different conditions, can be very similar. The primary (and consistent) difference between food intolerance and food allergy is that food intolerance doesn't prompt the immune system's release of IgE.

Allergic reactions to food share common traits with other allergic reactions: sneezing, wheezing and watery eyes, among others. Kids who have severe allergic reactions may break out in hives, have trouble breathing and require emergency medical care. As scary as this is, the overall number of children dying from food allergies is relatively low: about 150 a year. About 120 of these are caused by allergic reactions to peanuts, which are the food allergen most likely to cause anaphylaxis [source: Schwartz]. Many schools have banned peanut products outright.

Food allergies don't manifest on a child's first introduction to a food (though they often do on the child's first known introduction to the food). So while parents may hover over a small child the first time he or she consumes peanuts, it may be sometime down the road when the allergy presents itself. On the flip side, while some food allergies stick around for the duration of a person's lifetime, other times, they resolve themselves.

Children's food allergies can be frightening for child and parent alike, but proper diagnosis, allergy education and due diligence can lower both the risk and the worry associated with children's food allergies.

Next: Move over, Rover. No, seriously, get out.

Boy's best friend, perhaps, but not the best friend to his immune system.
Boy's best friend, perhaps, but not the best friend to his immune system.

Many parents get their feet wet raising kids by first raising pets. However, when the real thing comes along, sometimes the two just don't mix. Pet allergies in children can cause wheezing, runny noses, sneezing, watery eyes, coughing, itching and rashes. This can present a heart-breaking dilemma for many parents, who must choose whether to find a new home for the pet, or a new home for the child. Even if there's no pet in the family home, pet allergies can cause lots of problems for children who will be around animals when they're out and about or visiting the homes of relatives and friends.

Interestingly, it's not really the pet hair that causes allergic reaction in children -- it's the saliva, feces, dead skin cells and urine contained on that hair that does (or, more specifically, a certain protein found within the animal matter).

Not all animals will trigger an allergic reaction. Some kids are more allergic to cats, or to dogs (or to hamsters, or to guinea pigs). However, all breeds have the potential to cause an allergic reaction -- there's no "allergy-free" type of cat or dog.

If you suspect one of your pets is causing an allergic reaction, your best option is to have your kid checked out by an allergist immediately. If a doctor determines your son or daughter definitely has pet allergies, the best thing to do is keep the kid but find a new home for the pet. Understandably, the family's (or specifically the child's) attachment to the pet makes this a traumatic option. Nonetheless, it's the best thing to do for your child's health.

If, for any reason, the pet remains with the family, don't allow the animal into or near the child's bedroom. It's far more preferable to keep the pet out of the house entirely. Either way, since dander gets tracked into the house on clothes, hands and shoes, be sure to clean frequently, getting rid of all dander, hair and dust. Bathe the pet frequently, the more often the better -- weekly washing of pet can reduce allergic reactions by 84 percent [source: Humane Society]. Children can also be given allergy treatments, from allergy shots and nose sprays to antihistamine pills.

Next: Kids like their sports extreme, not their allergies.

As we've discussed, for most kids, having allergies is little more than a nuisance that requires a little prevention and precaution. Some children, however, have it a little harder. Extreme allergies can require frequent hospitalizations, visits to the allergist and daily oral medications or shots. In these cases, a bee sting or even a peanut can trigger severe reactions that present the risk of death.

Speaking of peanuts, they're rightly known as one of the biggest offenders when it comes to extreme allergies. About four out of five deaths from food allergies are attributed to peanuts.

Learning your child has extreme allergies (most often by witnessing alarming allergic episodes) is frightening for parents and kid alike. Sometimes these reactions take the form of an extreme case of eczema (skin rash) that can cover most of the body and even appear purple in color. During extreme allergic reactions, children may experience a sudden spike or drop in blood pressure. Anaphylactic reactions are a constant threat, and epinephrine injection pens should be an ever-present accessory at home or out and about. Fortunately, there are treatments and protective steps you can take (like carefully monitoring your child's contact with problematic foods) to greatly reduce the frequency and intensity of extreme allergic episodes.

While some allergies may be followed by a parental guessing game to determine if that was in fact an allergic reaction, extreme allergies are very self-evident. Any child with signs of allergies should receive a medical examination, and this goes double for kids who have symptoms of extreme allergies. Your pediatrician will be happy to refer you to a local allergist who will likely be a regular -- and welcome -- part of your child's life.

Related HowStuffWorks Articles


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