allergy


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Related to allergy: asthma, food allergy

al·ler·gy

(al'er-jē),
1. Hypersensitivity caused by exposure to a particular antigen (allergen) resulting in a marked increase in reactivity to that antigen on subsequent exposure, sometimes resulting in harmful immunologic consequences.
See also: allergic reaction, anaphylaxis, immune. Synonym(s): acquired sensitivity, induced sensitivity
2. That branch of medicine concerned with the study, diagnosis, and treatment of allergic manifestations.
3. An acquired hypersensitivity to certain drugs and biologic materials.
[G. allos, other, + ergon, work]

allergy

/al·ler·gy/ (al´er-je) a hypersensitive state acquired through exposure to a particular allergen, reexposure bringing to light an altered capacity to react. See hypersensitivity. aller´gic
atopic allergy  atopy.
bacterial allergy  specific hypersensitivity to a particular bacterial antigen.
bronchial allergy  atopic asthma; see asthma.
cold allergy  a condition manifested by local and systemic reactions, mediated by histamine, which is released from mast cells and basophils as a result of exposure to cold.
contact allergy  see under dermatitis .
delayed allergy  see under hypersensitivity.
drug allergy  an allergic reaction occurring as the result of unusual sensitivity to a drug.
food allergy , gastrointestinal allergy allergy produced by ingested antigens in food, usually manifested by a skin reaction.
hereditary allergy  atopy.
immediate allergy  see under hypersensitivity.
latent allergy  that not manifested by symptoms but which may be detected by tests.
physical allergy  a condition in which the patient is sensitive to the effects of physical agents, such as heat, cold, light, etc.
pollen allergy  hay fever.
polyvalent allergy  see pathergy (2).
spontaneous allergy  atopy.

allergy

(ăl′ər-jē)
n. pl. aller·gies
1. A condition in which exposure to a substance, such as pollen, latex, animal dander, or a particular food or drug, causes an overreaction by the immune system that results in symptoms such as sneezing, itching, rash, and difficulty breathing or swallowing.
2. Informal An adverse sentiment; antipathy: an allergy to cocktail parties.

allergy

[al′ərjē]
Etymology: Gk, allos, other, ergein, to work
a hypersensitive reaction to common, often intrinsically harmless, substances most of which are environmental. More than 50 million Americans have allergic reactions to airborne or inhaled allergens, such as cigarette smoke, house dust, and pollens. Symptoms of mild allergies, such as those associated with rhinitis, conjunctivitis, and urticaria, can be suppressed by antihistamines, with glucocorticoids administered as supplements to primary therapy. Severe allergic reactions, such as anaphylaxis and angioedema of the glottis, can cause systemic shock and death and commonly require immediate therapy with subcutaneous epINEPHrine or IV steroids, such as dexamethasone. See also allergic reaction, allergy testing. allergic, adj.

allergy

Immunology
1. A state of hypersensitivity induced by exposure to a particular antigen/allergen, resulting in adverse immune reactions on subsequent re-exposure to the allergen. See Anaphylactic shock, Cross allergy, Food allergy, Hypersensitivity reaction, Latex allergy, Peanut allergy, Pseudoallergy.
2. The medical specialty dedicated to diagnosing and managing allergic disorders.

al·ler·gy

(al'ĕr-jē)
1. Hypersensitivity caused by exposure to a particular antigen (allergen) resulting in a marked increase in reactivity to that antigen on subsequent exposure, sometimes resulting in harmful consequences.
See also: allergic reaction, anaphylaxis, immune
2. That branch of medicine concerned with the study, diagnosis, and treatment of allergic manifestations.
3. An acquired hypersensitivity to certain drugs and biologic materials.
[G. allos, other, + ergon, work]

allergy

Hypersensitivity to body contact with a foreign substance (an ALLERGEN), especially grass or tree pollens, foods, dust, mites or certain metals such as nickel. The effect may take several forms, including weals (URTICARIA), DERMATITIS, ASTHMA or hay fever (ALLERGIC RHINITIS). Allergy is mediated by the E class of antibodies (IgE). An allergic response implies that there has been a prior contact with the allergen during which the immunological processes leading to the hypersensitivity have occurred. Susceptibility to allergy is often of genetic origin. The term derives from the Greek allos , other and ergon , work. See also ALLERGIC DERMATITIS.

allergy

the overreaction of the IMMUNE RESPONSE of the body to minute traces of foreign substances (antigens). The reaction is usually visible in the form of rashes, itching, breathing difficulties, etc. Many of these symptoms can be attributed to specific antigens; for example in hay fever, ANTIBODIES react against pollen (antigen) and cause local damage with the release of HISTAMINE. Antihistamine drugs are one method of counteracting the effects of histamine.

Allergy

Altered body reaction, usually hypersensitivity, as a response to exposure to a specific substance.
Mentioned in: Serum Sickness

allergy

an immune response induced by exposure to an allergen causing a harmful hypersensitivity reaction (allergic response) on subsequent exposure. See also immunity.

allergy

acquired or induced hypersensitivity; after an initial non-reactive exposure to an allergen, the individual shows a hypersensitivity reaction at all subsequent exposures; re-exposure to the specific allergen evokes a predictable reaction within minutes or hours; acquired hypersensitivity to certain drugs and biological products may predict anaphylaxis at a subsequent exposure

allergy 

A state of hypersensitivity induced by re-exposure to a particular antigen (called allergen), usually environmental, such as pollens, foods, microorganisms and drugs. See allergic conjunctivitis; hypersensitivity.

al·ler·gy

(al'ĕr-jē)
1. Hypersensitivity caused by exposure to a particular antigen (allergen) resulting in a marked increase in reactivity to that antigen on subsequent exposure, some-times resulting in harmful immunologic consequences.
2. An acquired hypersensitivity to certain drugs and biologic materials.
See also: allergic reaction, anaphylaxis
Synonym(s): acquired sensitivity.
[G. allos, other, + ergon, work]

allergy (al´urjē),

n a hypersensitive reaction to an allergen; an antigen-antibody reaction is manifested in several forms–anaphylaxis, asthma, hay fever, urticaria, angioedema, dermatitis, and stomatitis.
Enlarge picture
Manifestations of allergies.
allergy, cross-reactive,
n a condition in which a patient allergic to one medication will experience an allergic reaction to all other medications and their derivatives (i.e., cross-sensitivity between penicillin derivatives, cephalosporins and carbapenems). See also resistance, cross.
allergy, “spontaneous” clinical,
n See atopy.

allergy

an altered reactivity following second or subsequent exposure to antigen (allergen). See also hypersensitivity, allergic.

atopic allergy
hereditary predisposition to develop certain allergies. See atopy.
bacterial allergy
a specific hypersensitivity to a particular bacterial antigen, e.g. Mycobacterium tuberculosis; it is dependent on previous infection with the specific organism.
bronchial allergy
asthma.
cold allergy
a condition manifested by local and systemic reactions, mediated by histamine, which is released from mast cells and basophils as a result of exposure to cold.
delayed allergy
see delayed hypersensitivity.
drug allergy
see drug allergy.
drying-off allergy
see milk allergy (below).
food allergy
called also gastrointestinal allergy; see food hypersensitivity.
gastrointestinal allergy
see food allergy (above).
hereditary allergy
an allergy with a hereditary predisposition. The tendency to develop some forms of allergy is inherited, but the specific clinical form is not. IgE, formerly called reagin or reaginic antibody, may be involved. See also atopy.
induced allergy
allergy resulting from the injection of an antigen, contact with an antigen, or infection with a microorganism, as contrasted with hereditary allergy.
inhaled allergy
see atopy.
milk allergy
a hypersensitivity to the milk protein, α-casein. Signs, varying from urticaria to anaphylaxis, have occurred in Jersey cows when milk escapes from the udder into the bloodstream during the drying off period.
physical allergy
a condition in which physical agents, such as heat, cold or light, trigger an allergic response.

Patient discussion about allergy

Q. ALLERGIES what are they,who gets them,are they caused by pollen and food?

A. Allergy is the exaggerated and out-of-place reaction of the immune system to external substances or stimuli that are not harmful to the body, so the reaction actually damages the body instead of helping it.

The may be pollen and foods, as well as insect stings, drugs and almost any other substances.

You may read more here:
www.nlm.nih.gov/medlineplus/allergy.html
http://www.mayoclinic.com/health/allergy/AA99999

Q. what is the most common allergy? is it dust allergy?

A. thanks, I've heard of a new allergy treatment and trying to learn some more about the different kinds...

Q. what are the symptoms of Allergy?

A. from you question i understand that you think you might developed an allergy. so here is a web page with couple of videos explaining about allergies:
http://www.healthline.com/video/allergies

More discussions about allergy
References in periodicals archive ?
Unlike a common cold, which includes a sore throat, allergy symptoms linger for longer than two weeks, Farhadian said.
Contact the Food Allergy & Anaphylaxis Network for further insights and excellent publications at www.
Metcalfe, MD, chief of the Laboratory of Allergic Diseases at the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health, Bethesda, MD.
As an owner of an allergic dog, I know how expensive and frustrating it can be to treat dog allergies," said, Kathy Hrach, Editor of Allergy Dog Central and owner of Elsie, a 4-year-old allergic Boxer dog.
J Allergy Clin Immunol 109(suppl): S482-S489; doi: 10.
Knowing the facts about life-threatening allergies and understanding the need for awareness are the first steps to becoming an inclusive host," says Tonya Winders, President and CEO of Allergy & Asthma Network, the leading allergy and asthma patient education, advocacy and outreach organization.
This article reviews the impact of allergy and asthma, diagnostic options, "the allergy march," and ongoing research.
8220;As spring allergy season blooms in New York, our team is excited about the growth we're experiencing and the new Flatiron office represents our continued commitment to providing New Yorkers with world-class medical care in a friendly environment in Manhattan.
Beware of Allergy campaign highlights the increasing incidence and burden of food allergy and of severe allergic reactions such as anaphylaxis and calls on patients, healthcare professionals and pharmacists to familiarise themselves with how to recognise early and manage these diseases.
The prevalence of food allergy varies significantly based on geographical region, allergens tested, diagnostic criteria, population age and concurrent atopic conditions.
Allergy occurs when our immune system decides (for unknown reasons) to respond aggressively to something harmless, and allergy often involves a special type of antibody called IgE antibodies.
PEOPLE with allergies are being let down by a lack of information and help, claims charity Allergy UK.