title: Olanzapine: evaluation of the in vivo cytogenetic effect.
abstract: OBJECTIVE
  Olanzapine (OLZ), an atypical antipsychotic, is licensed for use in the treatment of schizophrenia and other psychiatric disorders.
  
  
  METHODS
  OLZ cytogenetic effects were investigated by evaluating the frequency of Sister Chromatid Exchanges (SCEs) and Proliferation Rate Index (PRI) in cultured lymphocytes of schizophrenic patients who were under treatment of OLZ. SCE estimation is one of the most sensitive biomarkers of potential cytotoxicity, while PRI is used as a valuable marker of cytostatic activity.
  
  
  RESULTS
  Our results showed a statistically significant increase of SCEs in the cultured lymphocytes of patients (p < 0,001) compared to the lymphocytes of healthy donors, a statistically significant increase of SCEs (p < 0.001) in the lymphocytes of smoker patients compared to those of non-smoker patients and a statistically significant increase of SCEs (p < 0.001) in the lymphocytes of chronic recipients of OLZ compared to those of the patients with recent initiation of treatment. We did not detect any statistically significant differences with respect to PRI between the various groups examined.
  
  
  CONCLUSIONS
  Our results indicate a mild cytotoxic-but not cytostatic-effect of OLZ which was more prominent in smokers and in chronically treated patients. That effect should be taken into consideration by psychiatrists upon assessing the benefit/risk ratio of their prescriptions.
authors: Laboratory of General Biology and Genetics, Medical School, Aristotle University of Thessaloniki, Greece.
authors: Zampas
authors: Z
authors: Constantinos
authors: Papadopoulou
authors: P
authors: Eleni
authors: Antonis
authors: A
authors: Goulas
authors: Zafiroula
authors: Z
authors: Iakovidou-Kritsi
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001569:Benzodiazepines / Q000009:adverse effects* / Q000627:therapeutic use; D016022:Case-Control Studies; D049109:Cell Proliferation / Q000187:drug effects; D020732:Cytogenetic Analysis; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects*; D008297:Male; D000077152:Olanzapine; D012559:Schizophrenia / Q000188:drug therapy; D012854:Sister Chromatid Exchange / Q000187:drug effects*; D012907:Smoking / Q000009:adverse effects
chemical_list: D014150:Antipsychotic Agents; D001569:Benzodiazepines; D000077152:Olanzapine
keywords: cytogenetic activity; olanzapine; sister chromatid exchanges