What Causes Allergies in Children?
Allergies are extremely common; it has been estimated that more than 50 million Americans suffer from them. Allergies are an overreaction of part of the body's immune system, that complex network of special cells and tissues, which normally help protect the body from foreign substances. The body's immune system misinterprets some substances that are usually harmless as being foreign or potentially harmful. As a result, the immune system makes substances such as IgE antibodies and histamine, which are released into the blood stream to fight off these foreign or potentially harmful substances. This starts an inflammatory reaction in different parts of the body, and allergy symptoms develop. Some organs that can be affected by allergic reactions are the eyes, nose, skin, lungs and the digestive system.
The substances that trigger an allergic reaction of the immune system are known as allergens. Common allergens are foods (especially milk, eggs, nuts, soy, wheat, berries, fish and shellfish), venom from certain insects (wasps, bees), pollen from trees and plants (ragweed, grass), animal dander (from dogs, cats, horses, rabbits, guinea pigs), house dust mites, mold spores, certain chemicals (for example, cigarette smoke), and some medications, especially antibiotics. Allergies tend to run in families; they're commonly seen in people who also have the allergic skin condition eczema or the allergic lung condition asthma.
Symptoms and Signs of Allergies
Allergies can cause many different symptoms depending on the age of the child and which organ in the body is affected by the allergic reaction.
- An allergic reaction may affect the skin, causing a rash. Hives, with itchy, raised red welts, are a common allergic rash.
- Allergies of the digestive system may cause nausea, vomiting, diarrhea, and stomach cramps.
- Allergies affecting the nose are the most common, and are usually due to allergens that are inhaled.
- Nasal allergies, called hay fever or allergic rhinitis, may cause a stuffy or runny nose, sneezing, red watery eyes, and cough.
- Young children with allergies may have symptoms of asthma: rapid, shallow breathing, wheezing (a whistling exhalation), and a dry cough.
Anaphylactic Allergic Reactions
In rare cases, an allergic reaction can be life-threatening; this is called anaphylaxis. An anaphylactic reaction can be severe and happen quickly, usually involving more than one part of the body; it can become life threatening if treatment is not started right away.
The first symptoms are often itching and a burning or tingling feeling in the mouth, lips, and throat. There may be facial swelling around the eyes, mouth, and lips, which often is followed by a generalized rash in the form of hives. The mucous membranes in the mouth and throat may swell, causing difficulty in swallowing and breathing.
Anaphylaxis can also affect the circulation, and the child's skin can become pale, cold, and sweaty. The pulse increases as blood pressure falls, and the child will be in danger of fainting. Other symptoms of anaphylaxis are stomachache, vomiting, diarrhea, cramps, and lethargy.
How to Prevent Allergies
If it is impossible to completely avoid the substance to which a child is allergic, it is important to minimize the child's exposure to the allergen.
- In known cases of allergy to house dust mites, avoid wall-to-wall carpets, curtains, and stuffed animals in the child's bedroom. Use allergy covers for pillows and mattresses. Clear away toys and store them in a cupboard. Clean all rooms in the house regularly.
- Children with allergies to dogs or cats should not have these pets indoors and should be kept away from such animals when visiting friends and family. Be sure to tell all relatives, friends, and the child's school if the child is allergic to certain foods, especially in the case of a peanut allergy.
- Children allergic to pollen should not sleep with bedroom windows open during the pollen season and should shower and wash their hair before bedtime to remove as much pollen as possible. Air conditioning can be helpful during summer allergy season.
- Keep all children with known allergies away from cigarette smoke, as this can worsen the child's allergy symptoms. Avoid public places where people are smoking.
Treatment for Allergies
If you suspect that your child may have allergies, talk with a doctor, who may be able to diagnose allergies by examining your child and reviewing her symptoms and medical history. In some cases, the doctor may order some blood or skin tests to make a diagnosis. If there are signs of asthma, lung function testing might also be appropriate.
When symptoms persist despite these measures, various allergy medications are available. For example, some antihistamines block the immune system from releasing histamine into the blood, stopping allergic reactions before they start or slowing them down once they have begun. Steroids work to decrease the inflammation caused by the immune reaction; these can be in the form of nasal sprays, eyedrops, and pills or liquids taken orally. Allergy shots, the injection of tiny doses of an allergen, are helpful for some patients; they work by producing antibodies against the allergen, preventing severe allergic reactions in the future.
Children who have previously had an anaphylactic or serious allergic reaction should carry a dose of epinephrine that can be injected by the child or by his parents in case of an allergic reaction. Epinephrine is a hormone that helps to open up the airways to improve breathing, improve blood pressure, and decrease the allergic reaction. Whenever this medication is used, the child should be taken to an emergency room immediately.
Copyright © 2012 Meredith Corporation.
All content on this Web site, including medical opinion and any other health-related information, is for informational purposes only and should not be considered to be a specific diagnosis or treatment plan for any individual situation. Use of this site and the information contained herein does not create a doctor-patient relationship. Always seek the direct advice of your own doctor in connection with any questions or issues you may have regarding your own health or the health of others.