Cyclizine Products | Cleanchem - Cyclizine is an antihistamine used to prevent and treat nausea, vomiting, and dizziness associated with motion sickness, vertigo, and postoperative recovery. It works by blocking H1 histamine receptors and has mild anticholinergic and antiemetic properties. It is often used for nausea due to inner ear disturbances. Sedation and dry mouth are common side effects.