Chemically,<unk>  is the active levorotary enantiomer of cetirizine, also called the l-enantiomer of cetirizine. It is a member of the diphenylmethylpiperazine group of antihistamines.
Levocetirizine
Cetirizine
Ethacizine
Trifluoperazine
Meclizine
Benadryl
Loperamide
Dexlansoprazole