2.3. Side Effects: Parkinsonism is rated with the Simpson-Angus Scale for extrapyramidal side effects (SAS, Simpson and Angus, 1970). The Abnormal Involuntary Movement Scale (AIMS) (Guy, 1978) is chosen to assess tardive dyskinesia (TD) severity. All of the AIMS and Simpson-Angus Rating Scales are administered by the same investigator, at screening, at week-4, at week-1, at baseline and at baseline and at every two weeks, for a total of 12 ratings.