A patient develops an allergic reaction after repeated exposure to a new medication. Which mechanism explains why subsequent exposures trigger a more severe response?

💡 Explanation

IgE sensitization causes mast cells to bind IgE antibodies after the initial exposure; because subsequent exposures cross-link these IgE molecules, it triggers mast cell degranulation and a rapid release of histamine and other inflammatory mediators, therefore leading to a more pronounced allergic reaction, rather than a shift in drug metabolism or absorption.

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