Allergies
Description of Allergies:
Allergy is a disorder of the immune system often also referred to as atopy.
Allergic reactions occur to environmental substances known as allergens; these
reactions are acquired, predictable and rapid. Strictly, allergy is one of four
forms of hypersensitivity and is called type I (or immediate) hypersensitivity.
It is characterized by excessive activation of certain white blood cells called
mast cells and basophils by a type of antibody known as IgE, resulting in an
extreme inflammatory response. Common allergic reactions include eczema, hives,
hay fever, asthma, food allergies, and reactions to the venom of stinging
insects such as wasps and bees.
Mild allergies like hay fever are highly prevalent in the human population
and cause symptoms such as allergic conjunctivitis, itchiness, and runny nose.
Allergies can play a major role in conditions such as asthma. In some people,
severe allergies to environmental or dietary allergens or to medication may
result in life-threatening anaphylactic reactions and potentially death.
A variety of tests now exist to diagnose allergic conditions; these include
testing the skin for responses to known allergens or analyzing the blood for the
presence and levels of allergen-specific IgE. Treatments for allergies include
allergen avoidance, use of anti-histamines, steroids or other oral medications,
immunotherapy to desensitize the response to allergen, and targeted therapy.
Specific Allergies Information
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