In contrast to MACRILEN, a growth hormone (GH) secretagogue receptor agonist indicated for the diagnosis of adult growth hormone deficiency, MK677 is a research molecule and not approved for human consumption. These are a class of experimental substances popular among bodybuilders called SARMs, (selective androgen receptor modulators) and why are they so popular? they seem to be cleaner than steroids and they are oral. MK677 is a ghrelin agonist whichpromotes the natural production of human growth hormone (a hormone primarily associated with muscle growth and cell regeneration. The complex nature of regeneration means not 1 single hormone can regenerate the human body. A light androgenic affect and popular among the aging to get a subtle hormone bump before gym, MK677. Start at 5mg and titrate up or down. Bodybuilding cycles are usually 6 to 8 weeks and do blood test to learn the drug.