IL-6 is a soluble mediator with pleiotropic effects on inflammation, immune response, and hematopoiesis. The various functions of IL-6 were first studied and given different names based on their biological activities. For example, the name B cell stimulating factor 2 (BSF-2) was based on the ability to induce the differentiation of activated B cells into antibody (Ab)-producing cells (Kishimoto 1985), on the effect of acute phase protein synthesis on hepatocytes, the name hybridoma growth factor (HGF) to enhance the growth of fusion cells between plasma cells and myeloma cells or the name interferon (IFN)-β2 due to its antiviral IFN activity. Aim of the study: to evaluate the role of IL-6 in the induction of the liver monooxygenase system.