title: The effects of classic antipsychotic haloperidol plus the extract of ginkgo biloba on superoxide dismutase in patients with chronic refractory schizophrenia.
abstract: OBJECTIVE
  To explore the association between schizophrenic symptoms and superoxide dismutase (SOD), and to investigate the effect of classic antipsychotic haloperidol plus the extract of Ginkgo biloba (EGb) on SOD.
  
  
  METHODS
  In 54 patients with chronic refractory schizophrenia, 27 were treated with haloperidol plus EGb (group 1), and the rest received haloperidol plus placebo (group 2). Superoxide dismutase (SOD) levels of these patients were measured before and after treatment and compared with the levels of 25 healthy volunteers. Therapeutic efficacy was equated with a change in clinical rating scores assessed by standardized measurement tools including the Scale for Assessment of Positive Symptoms (SAPS) and the Scale for Assessment of Negative Symptoms (SANS).
  
  
  RESULTS
  Patients in group 1 improved significantly as demonstrated by scores from both SAPS and SANS, while those in group 2 only by scores from SANS. Assessed by SAPS, the response of patients receiving haloperidol plus EGb was more significant than those receiving haloperidol only. SOD levels before treatment in all patients were significantly higher than those in normal controls. After treatment, SOD levels decreased significantly in group 1 but not in group 2. In addition, before treatment, SOD levels in all patients correlated significantly with SAPS score. The levels of SOD measured before treatment were also correlated with the improvement of patients as measured by SAPS and SANS after 12 weeks.
  
  
  CONCLUSIONS
  EGb may enhance the efficacy of classic antipsychotic haloperidol on schizophrenia, especially on positive symptoms. It may work through an antioxidant efficacy that is involved in the therapeutic mechanism.
authors.affiliation: Department of Biochemistry, Institute of Mental Health, Beijing Medical University, Beijing 100083, China. zboudf@public.fhnet.cn.net
authors.forename: D
authors.initials: D
authors.lastname: Zhou
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.forename: J
authors.initials: J
authors.lastname: Su
authors.forename: Z
authors.initials: Z
authors.lastname: Nan
authors.forename: Y
authors.initials: Y
authors.lastname: Cui
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: Z
authors.initials: Z
authors.lastname: Guan
authors.forename: P
authors.initials: P
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: Shen
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000008:administration & dosage*; D004359:Drug Therapy, Combination; D005260:Female; D020441:Ginkgo biloba; D006220:Haloperidol / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008517:Phytotherapy; D028321:Plant Preparations / Q000008:administration & dosage*; D012559:Schizophrenia / Q000188:drug therapy* / Q000201:enzymology; D013482:Superoxide Dismutase / Q000097:blood*
chemical_list: D014150:Antipsychotic Agents; D028321:Plant Preparations; D013482:Superoxide Dismutase; D006220:Haloperidol