Effect of Buspirone added to Typical Antipsychotics on Positive and Negative symptoms in schizophrenia

INTERVENTION: Intervention 1: Typical Antipsychotics combined with Tablet Buspirone(30 mg/day) as intervention group for 6 weeks. Intervention 2: Typical Antipsychotics combined with Tablets placebo as control group for 6 weeks. Treatment ‐ Drugs Typical Antipsychotics combined with Tablet Buspirone(30 mg/day) as intervention group for 6 weeks Typical Antipsychotics combined with Tablets placebo as control group for 6 weeks. CONDITION: Schizophrenia Schizophrenia. ; Schizophrenia PRIMARY OUTCOME: Severity of schizophrenia. Timepoint: Baseline and weeks 2‐4‐6 after begining of treatment. Method of measurement: Positive and Negative Syndrome Scale(PANSS). SECONDARY OUTCOME: Headache. Timepoint: Baseline and weeks 2,4,6 after begining of treatment. Method of measurement: Check list of adverse effects. Nausea. Timepoint: Baseline and weeks 2‐4‐6 after begining of treatment. Method of measurement: Checklist of adverse effects. Palpitation. Timepoint: Baseline and weeks 2‐4‐6 after begining of treatment. Method of measurement: Checklist of adverse effects. INCLUSION CRITERIA: INCLUSION CRITERIA:Age between 18‐65; Diagnosis of Schizophrenia based on DSMIV‐TR; Chronic Schizophrenia(over 2 years); Ongoing treatment with Typical Antipsychotics. Exclusion criteria:Allergic to Buspirone; Any chronic medical problem; Substance dependency; Any other Psychiatric Disorder in Axis I or II; Pregnancy or Breast feeding.