Children and Adolescents: Safety and effectiveness for use in children has not been established. Initial: 12.5-25 mg/day; increase to a target dose of 25-400 mg/day. Adult (usual): First day: 12.5 mg once or twice daily initially. If tolerated, daily dosage increments of 25 to 50 mg may be added to achieve a target dose of 300 to 450 mg/day by 2-4 weeks. If necessary may be further increased in steps of 50-100mg once or twice weekly. Maximum: 900 mg/day If dosing is interrupted for >48 hours, therapy must be re-initiated at 12.5-25 mg/day; may be increased more rapidly than with initial titration. Elderly: Dose selection and titration should be cautious. Discontinuation of treatment: Gradually reduce the dose over a 1- to 2-week period. If abrupt discontinuation is required, carefully monitor the patient for recurrence of psychotic symptoms