hydrOXYzine hydrochloride /hīdrok″səzēn/ , an antihistamine. ▪ INDICATIONS: It is prescribed for the relief of anxiety, nervous tension, hyperkinesis, itching, and motion sickness. ▪ CONTRAINDICATIONS: Known hypersensitivity to this drug is the only contraindication. ▪ ADVERSE EFFECTS: No serious adverse effects have been observed. Decreased mental alertness sometimes occurs.