A patient with a history of seasonal allergies experiences an anaphylactic reaction after receiving a new medication. Which mechanism explains this reaction, given prior sensitization to pollen?

💡 Explanation

The anaphylactic reaction following medication administration in a pollen-sensitized individual is due to the cross-linking of IgE antibodies on mast cells by the drug, because the medication shares structural similarity with pollen antigens, therefore triggering mast cell degranulation. This is IgE-mediated, rather than direct drug-induced histamine release, which does not require prior sensitization.

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