Interleukin 17 (IL-17) is described as a pro-inflammatory cytokine produced by activated CD4 cells. Evidence shows that IL-17 is highly up-regulated at sites of inflammatory tissues of autoimmune diseases and amplifies the inflammation through synergy with other cytokines, such as TNF (tumor necrosis factor) α. Therefore, targeting IL-17/IL-17R, IL-17-producing pathways or IL-17-mediated signaling pathways can be considered for future therapy in autoimmune diseases