A patient who has chronic allergies takes loratadine (Claritin) and develops a severe reaction to bee stings. The patient asks the nurse why the antihistamine did not prevent the reaction. What will the nurse say?

Question

Quizplus · Accepted Answer

Severe allergic reactions with symptoms of anaphylaxis are caused by mediators other than histamine, so the benefits of antihistamines are limited. H₁ blockers do not block the release of histamine, but this is not why they are not effective in anaphylaxis. Second-generation agents are as effective as first-generation agents in allergic reactions mediated by histamine; neither is effective for treating anaphylaxis.

A Patient Who Has Chronic Allergies Takes Loratadine (Claritin) and Develops