NCIt definition : A piperazine derivative with antihistamine, antiemetic, and anxiolytic properties.
Hydroxyzine's antihistaminic effect is due to its metabolite, cetirizine, a potent
H1 receptor antagonist and selective inhibitor of peripheral H1 receptors. This agent
competes with histamine for binding at H1-receptor sites on the effector cell surface.
The sedative properties of hydroxyzine occur as a result of suppression of certain
subcortical regions of the brain. Secondary to its central anticholinergic actions,
hydroxyzine may be effective as an antiemetic.;