MK-677 (also called Ibutamoren) increases the levels of growth hormone (GH) and insulin-like growth factor production (IGF-1). Ibutamoren increases the levels of growth hormone by mimicking the action of ghrelin, and also attaching with one brain's receptors for ghrelin (GHSR). GHSR activation stimulates the release of brain growth hormone. According to research Ibutamoren,