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Description: Allergic Rhinitis (Hay Fever)

Definition Allergic rhinitis is the set of symptoms that occur when you breathe in substances to which you are allergic. These substances are called allergens.

Seasonal Allergic Rhinitis—sometimes called hay fever or rose fever. It occurs during specific times of the year when allergens (usually pollens) to which you are allergic are in the air. Seasonal allergies are usually at their peak during spring and fall.

Perennial Allergic Rhinitis—caused by allergens such as chemicals, dust, dust mites, cockroaches, animal dander, mild spores, or, occassionally, certain foods. It may occur at any time during the year when you encounter these allergens.

Causes The symptoms of allergic rhinitis occur... More

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Allergic Rhinitis (Hay Fever)

Definition Allergic rhinitis is the set of symptoms that occur when you breathe in substances to which you are allergic. These substances are called allergens.

Seasonal Allergic Rhinitis—sometimes called hay fever or rose fever. It occurs during specific times of the year when allergens (usually pollens) to which you are allergic are in the air. Seasonal allergies are usually at their peak during spring and fall.

Perennial Allergic Rhinitis—caused by allergens such as chemicals, dust, dust mites, cockroaches, animal dander, mild spores, or, occassionally, certain foods. It may occur at any time during the year when you encounter these allergens.

Causes The symptoms of allergic rhinitis occur when your body's immune system responds excessively to an allergen. Common allergens include dust mites, pollen, animal dander, and molds. When you breathe in an allergen, cells in your nasal passages produce a chemical called histamine. Histamine causes your nose to feel itchy. Histamine also causes swelling and mucus production in the nasal passages.

Risk Factors A risk factor is something that increases your chance of getting a disease or condition.

Asthma Eczema Family members with allergic rhinitis, eczema, or asthma Food allergies Symptoms Allergic rhinitis can cause the following symptoms:

Dark circles under your eyes Headache Itching in the nose, eyes, throat, ears Postnasal drip and cough Red, watery eyes Runny nose, nasal congestion Sinus pressure Sneezing Diagnosis If you have the symptoms of allergic rhinitis, your doctor can try to find out which allergens you are allergic to. Your doctor may refer you to an allergist, if necessary.

Tests may include:

Skin Prick Test A tiny bit of an allergen is placed under the skin with a needle. Then the doctor watches to see if the skin in that area becomes raised or irritated. This can be done for multiple allergens at the same time.

RAST Testing A small sample of blood is taken and tested for a few or dozens of different allergens.

Provocation Testing You breathe in air containing an allergen, and the doctor watches to see if you have an allergic reaction, such as wheezing or trouble breathing.

Treatment The most effective way to treat allergic rhinitis is to avoid the offending allergen. Since this can sometimes be difficult or impossible, other treatments are available.

Treatments may include:

Medications Antihistamines - stop or reduce the production of histamine. They are usually taken as pills.

Decongestants - decrease congestion by constricting blood vessels. They can be taken as pills or as a nasal spray.

Mast Cell Inhibitors - nasal sprays that interfere with the chemical reactions leading to histamine release.

Topical Corticosteroids - nasal sprays that decrease swelling in the nasal passages.

Immunotherapy (also called allergy shots) Injections of very small amounts of selected allergens are gradually increased over weeks, months, or even years. The goal is to make your body's immune system less sensitive to those particular allergens.

Prevention The following strategies may help prevent allergic rhinitis:

Avoid outside activities during the time of year when the trees, flowers or molds to which you are allergic are blooming. Clean your air conditioner's filters regularly. Consider running an air purifier in your home, especially in your bedroom. Cover pillows and mattresses with vinyl covers to reduce your exposure to dust mites. Decrease or avoid outdoor activities on hot summer days, when ozone levels may exacerbate allergies. If you can't avoid having a furry pet, vacuum frequently. Try to keep your pet out of bedrooms and other rooms with carpets. Keep the windows of your house and car closed to keep pollen out. Stay inside during the morning hours, when pollen counts are highest. Use an air conditioner to reduce indoor humidity during the warmer months. This will prevent mold and mildew growth. Use fewer dust-collecting items such as curtains, bed skirts, carpeting, and stuffed animals, especially in your bedroom or in rooms where you spend most of your time. Use vacuum cleaners and air conditioners with HEPA filters to trap allergens. Wash bedding weekly in very hot water. Last reviewed: December 2003 by Elizabeth Smoots, MD.

RESOURCES: American Academy of Allergy, Asthma, and Immunology http://www.aaaai.org/ Joint Council of Allergy, Asthma, and Immunology http://www.jcaai.org/ SOURCES: Allergy: Principles and Practice. 5th ed. Mosby-Year Book, Inc., 1998. Conn's Current Therapy 2001. 53rd ed. W. B. Saunders Company, 2001. American Academy of Allergy, Asthma, and Immunology. Joint Council of Allergy, Asthma, and Immunology. National Institute of Allergy and Infectious Disease.

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