The definition of a possum, or opossum, is a tree-dwelling nocturnal marsupial with fur and a prehensile tail. A small Australian mammal that lives in a tree and only comes out at night is an example of a possum. possum. possum.
More than two thirds of patients who die of anaphylaxis do so within the first: half hour. ____, a harsh, high-pitched inspiratory sound, occurs when swelling in the upper airway closes off the airway; the swelling can eventually lead to total obstruction. Stridor.
Sometimes, however, anaphylaxis can occur a half-hour or longer after exposure. Anaphylaxis symptoms include: 1  Skin reactions, including hives along with itching, and flushed or pale skin (almost always present with anaphylaxis). 2  A feeling of warmth. 3  The sensation of a lump in your throat.