In fact allergies are reactions of the body which are basically for protection of the
body against invading pathogens.But when the
body mistakes even harmless things as allergens,it triggers an allergic reaction.For understanding the mechanism of an allergic reaction pls log on to the following website: http://www.drugdigest.org/DD/HC/AdditionalContent/0,4054,1,00.html
Britannica encyclopedia however says that allergies are a kind of autoimmune reaction.
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