Editing Hypersensitivity (section)

=== Etiology ===
[[File:Type I Hypersensitivity.webm|thumb|Type I hypersensitivity]]
Type I hypersensitivity occurs as a result of exposure to an antigen. The antigens are proteins with a molecular weight ranging from 10 to 40 kDa.<ref name=":4" /> The response to the antigen occurs in two stages: the sensitization and the effect stage. In the "sensitization" stage, the host experiences an asymptomatic contact with the antigen. Subsequently, in the "effect" period, the pre-sensitized host is re-introduced to the antigen, which then leads to a type I anaphylactic or atopic immune response.<ref name=":0">{{Citation|last1=Abbas|first1=Malak|title=Type I Hypersensitivity Reaction|date=2021|url=http://www.ncbi.nlm.nih.gov/books/NBK560561/|work=StatPearls|place=Treasure Island (FL)|publisher=StatPearls Publishing|pmid=32809396|access-date=2021-07-04|last2=Moussa|first2=Mohamed|last3=Akel|first3=Hassan}} {{CC-notice|cc=by4}}</ref>