Reactine

Cetirizine hydrochloride, an antihistamine, (IPA sɛ.ˈtɪɹ.ɪ.ˌzin) is a major metabolite of hydroxyzine, and a racemic selective H₁ receptor antagonist used in the treatment of allergies, hay fever, angioedema, and urticaria. The structural similarity of cetirizine to hydroxyzine, and its derivation from piperazine, attribute similar adverse reactions and properties to other piperazine derivatives.
See more at Wikipedia.org...

Cetirizine /ce·ti·ri·zine/ a nonsedating antihistamine used as the hydrochloride salt in the treatment of allergic rhinitis, chronic idiopathic [more]Reactine - Community and Resources