Allergies Health Channel

	Feature Article Illustrations for this article Click on an image below to enlarge Hives (urticaria) on the arm Hives (urticaria) on the chest Show all 10 photos Allergies Definition An allergy is an exaggerated immune response or reaction to substances that are generally not harmful. See also: Allergic reactions Allergy testing Allergy to mold, dander, dust Drug allergies Food allergies Hay fever Causes, incidence, and risk factors Allergies are relatively common. Both genetics and environmental factors play a role. Allergy is caused by an oversensitive immune system, which leads to a misdirected immune response. The immune system normally protects the body against harmful substances, such as bacteria and viruses. It reacts to substances (allergens) that are generally harmless and in most people do not cause a problem. But in a person with allergies, the immune response is oversensitive. When it recognizes an allergen, it releases chemicals, such as histamines. This causes itching, swelling, mucus production, muscle spasms, hives, rashes, and other symptoms, which vary from person to person. What part of the body is contacted by the allergen plays a role in the symptoms you develop. For example, allergens that are breathed in often cause a stuffy nose, itchy nose and throat, mucus production, cough, or wheezing. A food allergen can cause nausea, vomiting, abdominal pain, cramping, diarrhea, or a severe, life-threatening reaction. Allergies to plants often cause a skin rash. Drug allergies usually involve the whole body and can lead to a variety of symptoms. Some medical conditions, such as eczema and asthma, are linked to allergies. Continue reading this article

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Allergy to mold - dander - dust (2 Videos, 4 Images) (Doctor-Reviewed information)
Allergy-related symptoms can occur after you are around mold, certain animals or animal hair, dust, and other substances. These substances are usually found indoors and do not cause symptoms for most people. See also: Asthma; Allergic rhinitis. Reviewer: Donald Accetta, MD, MPH, President, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network.Date: 10/30/2006
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Anaphylaxis (8 Images) Average Rating: (Doctor-Reviewed information)
Anaphylaxis is a life-threatening type of allergic reaction. Reviewer: David A. Kaufman, M.D., Assistant Professor, Division of Pulmonary, Critical Care & Sleep Medicine, Mount Sinai School of Medicine, New York, NY. Review provided by VeriMed Healthcare Network.Date: 05/03/2006
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Allergic rhinitis (4 Videos, 3 Images) Average Rating: (Doctor-Reviewed information)
Allergic rhinitis is a collection of symptoms, predominantly in the nose and eyes, caused by airborne particles of dust, dander, or plant pollens in people who are allergic to these substances. When these symptoms are caused by pollen, the allergic rhinitis is commonly called hay fever. See also: Allergies; Allergy to mold, dander, dust; Asthma. Reviewer: Donald Accetta, MD, MPH, President, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network.Date: 10/30/2006
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Food allergy (6 Images) (Doctor-Reviewed information)
A food allergy is an exaggerated immune response triggered by eggs, peanuts, milk, or some other specific food. Reviewer: Donald Accetta, MD, MPH, President, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network.Date: 07/25/2007
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Hives (1 Video, 10 Images) (Doctor-Reviewed information)
Hives are raised, often itchy, red welts on the surface of the skin. They are usually an allergic reaction to food or medicine. Reviewer: Kevin Berman, MD, PhD, Associate, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network.Date: 04/12/2007
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Allergic reactions (10 Images) (Doctor-Reviewed information)
Allergic reactions are sensitivities to a specific substance, called an allergen, that is contacted through the skin, inhaled into the lungs, swallowed, or injected. Reviewer: David A. Kaufman, M.D., Assistant Professor, Division of Pulmonary, Critical Care & Sleep Medicine, Mount Sinai School of Medicine, New York, NY. Review provided by VeriMed Healthcare Network.Date: 05/03/2006
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Drug allergies (11 Images) (Doctor-Reviewed information)
Drug allergies are a group of symptoms caused by allergic reaction to a drug (medication. Reviewer: Donald Accetta, MD, MPH, President, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network.Date: 07/19/2007
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Allergy testing (2 Videos, 4 Images) (Doctor-Reviewed information)
Allergy tests are any of several tests used to determine the substances to which a person is allergic. Reviewer: Donald Accetta, MD, MPH, President, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network.Date: 07/17/2007
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Could You Be Allergic. in The Diet Dish - 361 days ago

Many people think they are allergic, but it could be a different reaction that is not actually an allergy. If you have a friend or family member who has an... Email  |  Save