What is allergic rhinitis?Allergic rhinitis is a reaction of the lining of the nose to particles in the air.
How does it occur?Allergic rhinitis occurs when the nose and usually also the ears, eyes, sinuses, and throat come into contact with allergy causing substances. The allergy-causing substances are called allergens. The most common allergens are pollens, molds, dust, and animal dander. Some allergens are present only during certain seasons, for example, ragweed (genus Ambrosia) in the fall. The allergic reaction they cause is called seasonal allergic rhinitis or hay fever. Other allergens are present year-round, such as the mite’s in house dust. These allergens cause a type of rhinitis called perennial allergic rhinitis.
When the lining tissues of the nose and sinuses come into contact with allergens, chemical
called histamine is released from cells in the nose. Histamine causes the nose lining to swell,
itch, and make too much mucus.
What are the symptoms?
Common symptoms of allergic rhinitis are
- Itchy, runny nose
- Nasal and head congestion
- Fatigue and lethargy
- Itchy throat
- Postnasal drainage
- Itchy, watery eyes.
- The first step is to try to avoid contact with the things you are allergic to. For example, using an air conditioner and special filters rather than an attic fan lessens the amount of pollen that gets into your home. Putting plastic covers on mattresses may help you avoid dust and mold. You may also cover pillows with plastic.
- The second step is treatment with medicine. Medications
Other possible symptoms include
How is it diagnosed?Your health care provider will ask about your symptoms, medical history, and family history. He may swab the lining of your nose to obtain a sample of mucus. About 50% of people with allergies have cells in their mucus that indicate allergy. It may take some detective work to figure out exactly what you are allergic to. You may have tests for specific allergies. For most people the best tests are skin scratch or prick tests. For these tests your health care provider or an allergy specialist places tiny amounts of suspected allergens under your skin and looks for reactions. These allergy tests will identify which of many possible allergens are causing your symptoms. In some cases you may have blood tests to look for antibodies to suspected allergens. Allergy tests are expensive. Your health care provider will probably recommend that you try treating your symptoms with medicine first. If medicines do not control your symptoms, you may need allergy tests.
How is it treated?
Antihistamines-stop the interaction between histamine and the receptors; block the action of histamine; usually taken as pills or syrup
Decongestants-decrease congestion by constricting blood vessels, taken as pills or as a nasal spray; use of the nasal spray may lead to rebound congestion
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. There are several steroid nose sprays that can be used daily to treat or prevent symptoms. Depending on your other allergy symptoms, a nose spray may be the first and only medicine you need.
Immunotherapy (Allergy Shots) and Sublingual Therapy
If your symptoms are severe in spite of medicines, your health care provider may suggest allergy shots. With immunotherapy, very small amounts of allergens are injected over weeks, months, or even years. The goal is to make your body's immune system less sensitive to those allergens.
There's another, similar type of treatment called sublingual immunotherapy. It involves placing small amounts of allergens under the tongue. This treatment is more popular in Europe. While it has shown to reduce symptoms in some studies, more research is needed.
How long will the effects last?If you have had allergies since you were a child, you will probably have them the rest of your life. New allergies can develop any time, even if you have not had allergies before. Allergy symptoms depend not only on the season and weather but also on location. This means your allergies may wax and wane, depending on where you are living.
How can I help prevent allergic rhinitis?There are no known ways to prevent the development of allergic rhinitis. Once allergies have developed, you can try to limit exposure to the things that cause them, for example, pollens or animals. In severe cases, you may need to move to another area, but you may develop allergies there as well. The following strategies may help prevent allergic rhinitis :
- Stay inside during the morning hours when pollen counts are highest.
- Avoid outside activities during the time of year when the trees, grasses, weeds, or molds are blooming.
- Keep the windows of your house and car closed to keep pollen out.
- Use an air conditioner to reduce indoor humidity and to prevent mold and mildew growth.
- Clean your air conditioner's filters regularly.
- Consider running an air purifier in your home, especially in your bedroom.
- Use vacuum cleaners and air conditioners with high efficiency particulate air (HEPA) filter to trap allergens.
- Decrease or avoid outdoor activities on hot summer days, when ozone levels may make your symptoms worse.
- Cover pillows and mattresses with vinyl covers to reduce your exposure to dust mites.
- Wash bedding weekly in very hot water.
- Use fewer dust-collecting items, such as curtains, bed skirts, carpeting, and stuffed animals, especially in your bedroom.
- If you can't avoid having a furry pet, vacuum frequently and keep your pet out of bedrooms and other rooms with carpets.
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