Ghrelin is a novel growth hormone (GH)releasing peptide, isolated from the stomach, which has been identified as an endogenous ligand for GH secretagogue receptor. The discovery of ghrelin indicates that the release of GH from the pituitary might be regulated not only by hypothalamic GHreleasing hormone, but also by ghrelin derived from the stomach. This peptide also stimulates food intake and induces adiposity through GHindependent mechanisms. In addition, ghrelin acts directly on the central nervous system to decrease sympathetic nerve activity. Thus, ghrelin plays important roles for maintaining GH release and energy homeostasis. Repeated administration of ghrelin improves body composition, muscle wasting, functional capacity, and sympathetic augumentation in cachectic patients with heart failure or chronic obstructive pulmonary disease. These results suggest that ghrelin has anticachectic effects through GHdependent and independent mechanisms. Thus, administration of ghrelin may be a new therapeutic strategy for the treatment of cardiopulmonaryassociated cachexia.