What characterizes anaphylactic shock?

Anaphylactic shock is characterized by a massive immune hypersensitivity response, which occurs when the body encounters an allergen to which it has become sensitized. This type of shock is a severe and rapid allergic reaction that leads to the release of large quantities of histamine and other inflammatory mediators from immune cells. As a result, significant vasodilation and increased vascular permeability occur, leading to profound hypotension (low blood pressure), swelling, and various systemic symptoms such as difficulty breathing, hives, and gastrointestinal distress.

This response is life-threatening and requires immediate medical intervention, typically involving the administration of epinephrine, which counteracts the effects of the histamine and helps stabilize the individual’s condition. The other options do not accurately characterize anaphylactic shock; for example, while loss of consciousness may occur if blood pressure drops significantly, it is not a defining feature of the shock itself, nor is increased body temperature typically associated. Stagnation of blood flow may happen in some cases, but it is not the primary issue in anaphylaxis, which centers around the immediate immune response.