Evidence-based medicine suggests that schizophrenia is associated with an inflammatory syndrome, but the extent to which this syndrome is normalized by antipsychotic treatment has yet to be determined.A systematic quantitative review of the effects of antipsychotics on peripheral cytokine levels in schizophrenia was performed, using follow-up studies providing in vivo cytokine assessments before and after treatment.We retrieved 23 studies (total of 762 subjects) which showed that antipsychotic treatment significantly increases plasma levels of soluble interleukin-2 receptor and reduces the plasma levels of interleukin-1β and interferon-γ.These results show that antipsychotics produce anti-inflammatory effects in schizophrenia.