Cytokines are regulatory polypeptides secreted during the generation of an immune or inflammatory response by lymphocytes, cells of the monocyte/macrophage series, and a variety of other cell types. Alterations in the production, site of action, or metabolism of cytokines by exogenous factors, such as ethanol (EtOH), may have deleterious effects on the immune system as a whole. EtOH has been implicated in the onset of a variety of immune defects in vivo including effects on the production of cytokines critically involved in inflammatory responses (tumor necrosis factor, interleukin 1 and interleukin 6). In this review, we examine current knowledge regarding the effects of EtOH on the release of cytokines in humans and in animal models, in vitro and in vivo, which may help to elucidate the adverse actions of EtOH on mammalian immune systems.