The Collaborative International Dictionary
systemic anaphylaxis
anaphylactic shock \anaphylactic shock\ n. (Med.)
a severe form of physiological shock, often having a fatal
outcome, caused by an extreme immunological reaction to
antigens. It is a severe form of anaphylaxis[2], and is
characterized by smooth muscle contraction and capillary
dilation throughout the body, initiated by antibodies of the
IgE class. It is usually seen when an antigen to which a
person has become hypersensitized is injected intravenously
or subcutaneously. It is also called generalyzed
anaphylaxis or systemic anaphylaxis, and sometimes
anaphylaxis.
--[Stedman]