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.
Anaphylaxis is the result of your body's immune system overreacting to a harmless substance, such as food. Substances that trigger allergic reactions are known as allergens. Anaphylaxis usually develops within minutes of contact with an allergen, but sometimes the reaction can happen up to four hours later.