To our knowledge, the relationship between changes in serum leptin, as a well-known adipose related factors, and S100B levels, as a surrogate marker for regulation of cellular energy metabolism, and symptoms improvement of schizophrenia and side effects associated with atypical antipsychotic drugs, specifically metabolic syndrome, have not been studied .In this study we evaluated the relationship between S100B and leptin, a well-known adipose related factor, in schizophrenic patients receiving clozapine and risperidone. This evidence concerns the gene S100B and schizophrenia.