The role of IL-6 has also been discussed in the etiopathogenesis of schizophrenia in terms of treatment-resistant schizophrenia being associated with increased IL-6 serum levels, an association between higher IL-6 levels and cognitive decline, that was established, and a decrease in serum levels of IL-6 following antipsychotic therapy (12). This evidence concerns the gene IL6 and schizophrenia.