allergic reaction

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pertaining to or having an allergy.
allergic reaction a local or general reaction characterized by altered reactivity of the animal body to an antigenic substance; see also allergy.

al·ler·gic re·ac·tion

a local or general reaction of an organism following contact with a specific allergen to which it has been previously exposed and sensitized; immunologic mechanisms gives rise to inflammation or tissue damage. Allergic reactions are classified into four major types: type I, anaphylactic and IgE dependent; type II, cytotoxic; type III, immune-complex mediated; type IV, cell mediated (delayed).

allergic reaction

an unfavorable physiological response to an allergen to which a person has previously been exposed and to which the person has developed antibodies. The response may be characterized by a variety of symptoms, including urticaria, eczema, dyspnea, bronchospasm, diarrhea, rhinitis, sinusitis, laryngospasm, and anaphylaxis. Allergic reactions may be immediate or delayed. Eosinophilia is usually present and is revealed in the differential white blood cell count.

allergic reaction

Immunology Any response to an allergic stimulus, which can be localized or systemic Clinical Rash, itching, hives, swelling, dyspnea, ↓ BP Lab ↑ IgE, ↑ mast cells, basophils, which release histamine, PGs, LTs, kinins, et al. See Asthma, Hypersensitivity reaction.

al·ler·gic re·ac·tion

(ă-lĕr'jik rē-ak'shŭn)
A local or general reaction of an organism following contact with a specific allergen to which it has been previously exposed and sensitized.

Allergic reaction

An inappropriate or exaggerated genetically determined reaction to a chemical that occurs only on the second or subsequent exposures to the offending agent, after the first contact has sensitized the body.

allergic reaction,

n aggravated immune system response to a variety of environmental and other substances, both chemical or organic. Reactions may be mild to life-threatening and include urticaria, eczema, dyspnea, bronchospasm, diarrhea, rhinitis, sinusitis, laryngospasm, and anaphlaxis.
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Allergic reaction.

al·ler·gic re·ac·tion

(ă-lĕr'jik rē-ak'shŭn)
Local or general reaction of an organism after contact with a specific allergen to which it has been previously exposed and sensitized.
Synonym(s): hypersensitivity reaction.


pertaining to or caused by allergy.

allergic alveolitis
allergic breakthrough
a theory which attributes temporary increases in clinical severity of atopy to influences, such as concurrent disease or hormonal variations, acting to inhibit the mechanisms which normally regulate production of IgE at low levels following sensitization.
allergic bronchitis
see bronchitis, feline bronchial asthma, pie syndrome.
allergic contact dermatitis
results from percutaneous sensitization to allergens, usually haptens, that form covalent bonds with epidermal proteins, and the development of a delayed (type IV) hypersensitivity. Lesions typically correspond in location to the area of contact between allergen and skin which in animals is often in relatively hairless areas unless the allergen is presented in liquid form.
allergic dermatitis
inflammation of the skin resulting from exposure to antigens to which the animal is hypersensitive. Usually involving immediate (type I) hypersensitivity but also commonly applied to reactions involving delayed (type IV) hypersensitivity. The specific skin reaction, lesions and pattern of disease produced depend on many factors including the type of allergen and immune mechanism, route of exposure and species differences. See also atopy, sweet itch, allergic contact dermatitis (above).
allergic encephalitis
see experimental allergic encephalomyelitis.
equine allergic dermatitis
an intensely itchy dermatitis along the back of horses caused by sensitivity to the bites of the sandfly Culicoides brevitarsus and possibly other insects. Called also sweet itch, Queensland itch.
allergic inhalant dermatitis
see atopy.
allergic reaction
an immune-mediated, adverse clinical response, following the inhalation, ingestion or injection of an antigen by a sensitized animal. Manifestations include urticaria or anaphylaxis.
allergic rhinitis
see enzootic nasal granuloma, summer snuffles.
allergic urticaria

Patient discussion about allergic reaction

Q. what cause an allergic reaction?

A. Frankly? no ones actually knows for sure. What we do know, is that due to some reason the immune system of certain people, regard several non-harmful substances (e.g. peanuts, antibiotics, bee's venom) as an enemy and learn to react to it.

This tendency to develop abnormal responses to substances other people don't response to is called "atopy". It has a very strong genetic basis (i.e. it runs in families), and also depends on other factors such as the exposure to infections and the pattern of exposure to the allergen (the substance that causes allergy).

It's a very wide subject, far beyond the scope of my answer, so you may read more here:

Q. Is it common to get an allergic reaction in the eye from olive harvest? I've been around olive trees for a few hours and now feel like I have something in my eye but there is nothing there. can it be an allergic reaction? I dont get it from eating olives...

A. but in one eye..? that just doesn't seem likely. but i guess there is no reason not to try both treatments....

Q. I am worried about the allergic reactions I had from the Chinese herbal drug. I am worried about the allergic reactions I had from the Chinese herbal drug that I took for my arthritis…..are these safe?

A. Many people have some type of reaction to either a drug and even a supplement. You can check with your doc to get tested to see what your sensitivities are. Regarding arthritis, no milk, cheese, yogurt, butter, anything with milk for starters, AVOID like the plague! Suagr consumption too will raise hell with it. There is a product that someone I knew took, called, "Cell Guard" which he bought at a health food store or Whole Foods. After a couple of months, he was pain free. Its worth a try! Cell Guard is made with SOD or "superoxide dismutase"
Studies have shown that SOD can play a critical role in reducing internal inflammation and lessening pain associated with conditions such as arthritis! Check it out! Let me know how you do!

More discussions about allergic reaction
References in periodicals archive ?
Higher the exposure time, more will be the chances of allergic reactions to residues.
Using the slit lamp, your ophthalmologist checks your eyes for dilated blood vessels, conjunctival swelling, and eyelid swelling, all of which are indicative of an allergic reaction.
The immune-pathogenesis of allergic reaction is proposed to be IgE mediated against glucocorticoid molecules.
It is therefore clear from the instructions that there is a risk of an allergic reaction and a number of warnings and precautions are highlighted.
Urticaria may be an allergic reaction to a food, such as shellfish, fruits and nuts.
Salons and home color kits make it easy to say goodbye to grey hairs and roots, but sudden serious allergic reactions to hair dye are on the rise--even among those who have been using the same hair coloring product for years.
Most symptoms of an allergic reaction go away shortly after the exposure stops.
The first step in preventing a severe allergic reaction is always avoidance of the specific allergen, said Dr.
Mine then monitored the mice for visible signs of an allergic reaction and also took blood and tissue samples to test the animals' levels of histamine and immunoglobulin E--substances produced by the body to induce allergic reactions.
And they were never sure whether Ms Arnold was actually suffering an allergic reaction or not.
A YOU may be sensitive to the air-conditioning which is causing an allergic reaction.
A protein in mice known as RGS13 suppresses allergic reactions, including the severe, life-threatening allergic reaction known as anaphylaxis, according to scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH).