Subjects who meet the inclusion and exclusion criteria and have no history of oral aripiprazole use will enter Phase A after the Screening Period while still hospitalized. Subjects in Phase A will be administered oral aripiprazole, as indicated in the product labeling, to determine tolerability. Dosage will be based on symptoms and the judgment of the investigator. The dose of oral aripiprazole may be titrated as needed. Prior antipsychotic medications will be tapered off and discontinued during the Screening Period and Phase A as clinically appropriate.