If a patient with a known bee sting allergy is stung, and epinephrine is unavailable, why does administering an H1 receptor antagonist (antihistamine) provide only limited relief?

💡 Explanation

Antihistamines block histamine's action at H1 receptors, but anaphylaxis involves multiple mediators released from mast cells, including leukotrienes, prostaglandins, and cytokines. Therefore, antihistamines only address histamine effects, rather than the broader inflammatory cascade initiated during a severe allergic reaction.

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