Allergies, such as allergic rhinitis, are a result of the immune system being overly sensitive to a compound that's harmless to most people. Children are especially prone to allergic rhinitis because their immune system is still developing, and the child may grow out of the allergy, according to the National Institutes of Health (NIH).
Cause
Allergic rhinitis is caused by exposure to substances called allergens, the American Academy of Otolaryngology explains. Allergens are normally harmless molecules which can provoke an abnormal immune response in susceptible people. Children are not born with any allergies; however, repeated exposure to certain substances can cause the immune system to become hypersensitive. In those cases, when the child is exposed to the allergen, the immune system has a powerful response and releases histamine, as well as a number of other chemicals. If the allergen is inhaled, the nasal passages become swollen and inflamed, leading to allergic rhinitis.
Symptoms
The main symptoms of allergic rhinitis, according to the NIH, are itching and redness of the nose, combined with running and congestion of the nose. Other parts of the face, including the mouth, eyes and neck, may also be affected. Children suffering from allergic rhinitis may also experience sneezing, impaired sense of smell and tearing eyes. Children with seasonal allergies, such as allergies to pollen, will only experience symptoms during some of the year. Children with allergies to dust mites or animal dander, on the other hand, may have allergic rhinitis year round.
Complications
One complication of allergic rhinitis in children is that the swelling of the nasal passages can lead to difficulty in breathing through the nose. This is due in part to the fact that the tonsils and adenoids gradually become larger with age, further blocking the nasal passages from the respiratory system. As a result, children may have problems with snoring, mouth-breathing and obstructive sleep apnea. Children with allergic rhinitis are also more prone to developing ear and upper respiratory infections.
Diagnosis
Allergic rhinitis is often suspected based on a history of nasal symptoms, particularly those that only occur during specific times of the year or which occur only in certain situations, such as exposure to animals or certain plants. Allergy testing is most commonly done using skin testing, the NIH explains. Skin testing involves placing a small amount of a suspected allergen on or just under the skin to see if it is able to generate an allergic reaction. If the area around the test sample becomes swollen and red, the patient is most likely allergic to the suspected allergen.
Treatment
The simplest way of treating allergic rhinitis, the Mayo Clinic notes, is simply to avoid allergens whenever possible. When this cannot be done, there are a variety of medications that can be used to relieve the symptoms of allergic rhinitis. These include antihistamines, which block the effects of histamine. Other compounds that block the immune activity which causes allergic rhinitis include corticosteroids and leukotriene modifiers. Patients may also receive allergy shots, which consist of a series of injections of a small amount of allergen. Allergy shots try to desensitize the immune system to the allergen via repeated exposure.
