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Alternative Names Return to top
Hay fever; Nasal allergiesDefinition Return to top
Allergic rhinitis is a collection of symptoms, mostly in the nose and eyes, which occur when you breathe in something you are allergic to, such as dust, dander, or pollen.
When these symptoms are caused by plant pollen, the allergic rhinitis is commonly called hay fever.
See also:
Causes Return to top
An allergen is something that triggers an allergy. When a person with allergic rhinitis breathes in an allergen such as pollen or dust, the body releases chemicals, including histamine. This causes allergy symptoms such as itching, swelling, and mucus production.
Hay fever involves an allergic reaction to pollen. (A similar reaction occurs with allergy to mold, animal dander, dust, and similar inhaled allergens.)
The pollens that cause hay fever vary from person to person and from region to region. Large, visible pollens are seldom responsible for hay fever. Tiny, hard to see pollens more often cause hay fever. Examples of plants commonly responsible for hay fever include:
The amount of pollen in the air can play a role in whether hay fever symptoms develop. Hot, dry, windy days are more likely to have increased amounts of pollen in the air than cool, damp, rainy days when most pollen is washed to the ground.
Some disorders may be associated with allergies. These include eczema and asthma.
Allergies are common. Your genes and environmental may make you more prone to allergies.
Whether or not you are likely to develop allergies is often passed down through families. If both your parents have allergies, you are likely to have allergies. The chance is greater if your mother has allergies.
Symptoms Return to top
Exams and Tests Return to top
The health care provider will perform a physical exam and ask you questions about your symptoms. Your history of symptoms is important in diagnosing allergic rhinitis, including whether the symptoms vary according to time of day or the season, exposure to pets or other allergens, and diet changes.
Allergy testing may reveal the specific substances that trigger your symptoms. Skin testing is the most common method of allergy testing. This may include prick, patch, or other tests.
If your doctor determines you cannot undergo skin testing, special blood tests may help with the diagnosis.
Treatment Return to top
The best treatment is to avoid what causes your allergic symptoms in the first place. It may be impossible to completely avoid all your triggers, but you can often take steps to reduce exposure.
There are many different medications available to treat allergic rhinitis. Which one your doctor prescribes depends on the type and severity of your symptoms, your age, and whether you have other medical conditions (such as asthma).
Specific illnesses that are caused by allergies (such as asthma and eczema) may require other treatments.
Treatments for allergic rhinitis include:
ANTIHISTAMINES
Antihistamines work well for treating allergy symptoms, especially when symptoms do not happen very often or do not last very long.
CORTICOSTEROIDS
DECONGESTANTS
OTHER TREATMENTS
ALLERGY SHOTS
Allergy shots (immunotherapy) are occasionally recommended if the allergen cannot be avoided and if symptoms are hard to control. This includes regular injections of the allergen, given in increasing doses (each dose is slightly larger than the previous dose) that may help the body adjust to the antigen.
Outlook (Prognosis) Return to top
Most symptoms of allergic rhinitis can be readily treated.
Some people (particularly children) may outgrow an allergy as the immune system becomes less sensitive to the allergen. However, as a general rule, once a substance causes allergies for an individual, it can continue to affect the person over the long term.
More severe cases of allergic rhinitis require allergy shots or removal of tissue in the nose or sinuses.
Possible Complications Return to top
When to Contact a Medical Professional Return to top
Call for an appointment with your health care provider if severe symptoms of allergies or hay fever occur, if previously successful treatment has become ineffective, or if your symptoms do not respond to treatment.
Prevention Return to top
Symptoms can sometimes be prevented by avoiding known allergens. During the pollen season, people with hay fever should remain indoors in an air-conditioned atmosphere whenever possible:
For people who are sensitive to certain indoor allergens, dust mite covers for mattresses and pillowcases are recommended, as well as avoiding culprit pets or other triggers.
References Return to top
Wallace DV, Dykewicz MS, Bernstein DI, Blessing-Moore J, Cox L, Khan DA, et al. The diagnosis and management of rhinitis: an updated practice parameter. J Allergy Clin Immunol. 2008 Aug:122(2).
Jen A, Baroody F, de Tineo M, Haney L, Blair C, Naclerio R. As-needed use of fluticasone propionate nasal spray reduces symptoms of seasonal allergic rhinitis. J Allergy Clin Immunol. 2000 Apr:105(4):732-8. Update Date: 1/9/2009 Updated by: Stuart I. Henochowicz, MD, FACP, Associate Clinical Professor of Medicine, Division of Allergy, Immunology, and Rheumatology, Georgetown University Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
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