Tranquilization refers to the act of bringing a state of calmness and relaxation to someone or something. Antonyms for the word tranquilization would, therefore, refer to the opposite state or action. One possible antonym is aggravation, which is the act of making something worse or causing irritation. Another antonym could be discomposure, which refers to a state of unrest or unease. Agitation, stress, and disturbance are other possible antonyms for tranquilization. These words connote a sense of worry, disturbance, and chaos, which is the complete opposite of the peaceful state that tranquilization aims to achieve.