Why does anaphylaxis cause bronchoconstriction and breathing difficulty, despite the body's attempt to increase ventilation?

💡 Explanation

Anaphylaxis triggers systemic mast cell degranulation, releasing histamine and other mediators that dramatically increase vascular permeability, causing airway edema, because this response obstructs airflow. Therefore, massive mast cell degranulation results in constricted airways, rather than bronchodilation from sympathetic drive, and it overwhelms compensatory mechanisms.

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