Vertazine was a drug typically administered in a hypospray to remedy dizziness.
Dr. Crusher gave La Forge a twenty cc dose of vertazine after he experienced an episode of dizziness while working in Main Engineering. (TNG: "Cause And Effect")
Whenever Worf transported between quantum realities he experienced dizziness. Following one transition, Dr. Crusher offered to give Worf some vertazine, to counteract the side effects of the concussion that he suffered in that quantum reality. (TNG: "Parallels")