Allergic rhinitis (commonly called hay fever) is an inflammation or irritation of the mucous membranes that line the nose. Common symptoms include sneezing; a stuffy or runny nose; itchy eyes, nose and throat; and watery eyes. You may also have a nasal voice; breathe noisily; snore; feel chronically tired; have a poor appetite; feel nauseated; have frequent headaches; and, have some difficulty hearing and smelling.

Causes
Allergic rhinitis happens when an allergen (an allergy-producing substance, such as pollen) causes your body to defend itself by producing antibodies. When an allergen and an antibody combine, your body releases histamine and other chemical substances into your bloodstream, which causes an allergic response. Pollen, dust, mold or other substances that can be inhaled, are common allergens that cause symptoms.

Seasonal allergic rhinitis usually results from tree, grass or weed pollen. With this type of rhinitis, symptoms will decrease with the arrival of cold weather.

Perennial allergic rhinitis can cause year-round symptoms. This allergic reaction is the result of indoor irritants such as feathers, mold spores, animal danders (hair and skin shed by pets) or dust mites.

Because different types of pollen, dust and mold spores exist in various geographic locations, you may suddenly develop allergic rhinitis, if you move.

Prevention
You cannot prevent an allergy, but you can prevent a reaction. The most effective method you can use to prevent a reaction is to avoid the allergen that triggers your allergic response. Try these steps as well:

• If you are allergic to warm-blooded animals, confine your pet to a particular area of your home. It is especially important to keep warm-blooded pets out of the bedroom. If the effects on your health are severe, consider giving your pet away.

• Avoid pollen by using air conditioning, by avoiding outside activity during pollen season, and by timing your vacations away from home to benefit your health.

• Check the material from which your pillows and comforters are made. Feathers, foam rubber, or pillows more than five years old are often allergens.

• Avoid dust and mold. Since this is difficult and it may be impractical for you to create an "allergy-proof" home, at least make sure your bedroom is as allergen-free as possible:

  • move out all unnecessary furniture

  • keep windows tightly shut

  • frequently clean the curtains, blinds, bedding and carpeting

  • use pillows and comforters stuffed with dacron or polyester

  • enclose mattresses and box springs in plastic

  • cover or filter all vents

  • purchase a HEPA filter for your sleeping area and possibly for other areas of your home

  • move out decorative pillows, books, and stuffed animals

  • keep the floors bare

  • use dusting products formulated to hold the dust

  • store clothing so dust will not settle on it

  • never sweep - use a vacuum only

These tips may also decrease the severity of your allergic reaction and for increasing your comfort:

• Maintain a balanced diet to improve your body's ability to heal itself

• Sleep with your head elevated to prevent nasal congestion during the night

• Drink adequate fluids (eight 8-ounce glasses per day) to loosen the secretions in your nose and throat

• Exercise regularly

Diagnosis
It is not always easy to diagnose allergic rhinitis. Many symptoms are similar to those of a cold so, if you use cold preparations, you may seem to improve for short periods of time. You and your practitioner may notice that you have symptoms every August (or May) and that the symptoms last for about the same amount of time each year. If you have perennial allergic rhinitis, it is even harder to diagnose because there is no clear pattern of illness. Sometimes your practitioner may order blood and skin tests to determine whether or not you have an allergy.

Treatment
The best treatment for your allergy is to avoid the allergen. When this is not possible, medication can usually control the symptoms of a reaction. Because each individual is unique, there is no standard treatment for allergic rhinitis. The best medication can only be determined by you and your practitioner. It may take several trials for you to determine the best medication and the optimal dosage.

These medications are used to treat allergic rhinitis:

• Antihistamines block the action of the histamine (the substance which triggers the reaction). They are considered the "mainstay of treatment." They are more effective when taken around the clock. They can cause you to become drowsy, especially if you combine them with alcohol. Other side effects include dizziness, blurred vision, insomnia, tremors, nausea and dry mouth. If any of the side effects are a problem, discuss them with your practitioner.

• Decongestants can give short-term relief from nasal stuffiness. However, many decongestants promote histamine release. This can cause a "rebound" effect that ultimately makes you even more congested than before. Use them only on a short-term, special occasion basis (i.e., unable to sleep for several nights, a test, a date, etc.).

• Corticosteroids may lessen your allergic reaction by preventing body cells from responding to histamine. For allergic rhinitis, these compounds are administered via a nasal spray. Minimal side effects have been found even with chronic use at customary dosage. For profound allergy symptoms, a one-time very short course of systemic cortisteroid may be considered as a last resort.

• Cromolyn sodium inhibits the body's release of histamine after exposure to an antigen, which can lessen or stop the allergic response. If you are allergic to a substance that you are exposed to occasionally, you would only take this medication prior to exposure. Side effects are minimal. Unfortunately, not everyone is helped by this medication.

• Immunotherapy or (allergy shots) are also used in cases of allergic rhinitis. It is effective only when a specific allergen can be identified. Some ragweed and pollen allergies respond well to this treatment. Since you are allergic to the substance injected, you may experience severe allergic responses. Therefore, if you undergo immunotherapy, you should work closely with your physician and report any symptoms of reaction to the injection. Immunotherapy is not a "quick fix" and may take six months before effectiveness is noted. It is very helpful for many people.

Information provided by: http://www.mckinley.uiuc.edu