exactly what is Swiss Chems MK677 Ibutamoren? MK-677, also known as ibutamoren or ibutamoren mesylate, is actually a peptide that belongs to the growth hormone secretagogues team (GHSR). it really works by mimicking the motion in the starvation hormone ghrelin. It binds to one of the growth hormone secretagogue receptors (GHSR) while in the brain,