If a patient with a known bee sting allergy is stung again, which consequence follows due to histamine's effect on endothelial cells?

💡 Explanation

Systemic vasodilation and hypotension occur because histamine released during mast cell degranulation increases vascular permeability via endothelial cell contraction, therefore fluids leak from capillaries into tissues causing a drop in blood pressure, rather than localized vasoconstriction.

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