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Allergic reaction

Allergic reaction – the general name of clinical manifestations of hypersensitivity of an organism to allergen.


  • Allergic reaction of the slowed-down type (a synonym: kitergichesky reaction) – develops for 24-48 hours from the beginning of influence of offending allergen. The main role in formation of allergic reaction of the slowed-down type is played by interaction of allergen with sensibilized lymphocytes. Allergic reaction of the slowed-down type exerts considerable impact on a pathogeny of some infectious diseases (a brucellosis, tuberculosis, a leprosy, etc.) and in the graft rejection mechanism;
  • Allergic reaction of immediate type (synonym: himergichesky reaction) – develops 15-20 minutes later after influence of offending allergen, for example, in case of an acute anaphylaxis. The main role in emergence of allergic reaction of immediate type belongs to interaction of allergen with allergic antibodies (reagins);
  • Allergic cross-reaction – arises on the cross reacting (general) antigens;
  • Allergic reaction system – is most brightly shown in any system of bodies.
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