anaphylaxis

/ˈænəfəˌlæksəs/

Definitions of anaphylaxis

1. noun

   hypersensitivity reaction to the ingestion or injection of a substance (a protein or drug) resulting from prior contact with a substance
   types:

   anaphylactic shock

   a severe and rapid and sometimes fatal hypersensitivity reaction to a substance (especially a vaccine or penicillin or shellfish or insect venom) to which the organism has become sensitized by previous exposure

   type of:

   hypersensitivity reaction

   an inappropriate and excessive reaction to an allergen (as pollen or dust or animal hair or certain foods); severity ranges from mild allergy to severe systemic reactions leading to anaphylactic shock