Hydroxyzine blocks the activity of histamine to relieve allergic symptoms such as pruritus. Activity at off-targets also allows for its use as a sedative anxiolytic and an antiemetic in certain disease states. Hydroxyzine is a medication that acts as an H1-blocker, originally used for allergies and motion sickness. It can cross the blood-brain barrier, affecting dopamine and serotonin receptors, leading to sedative and anxiolytic effects.