A series of compounds possessing both H1 histamine receptor antagonist and 5- lipoxygenase (5-LO) inhibitory activities was synthesized. The H1-binding scaffolds of cetirizine, efletirizine, and loratadine were linked to a lipophilic N-hydroxyurea, the 5-LO inhibiting moiety of zileuton. Both activities were observed in vivo, as was increased CYP3A4 inhibition compared to their respective single-function drugs. Selected analogs in ...