What is Swiss Chems MK677 Ibutamoren? MK-677, often known as ibutamoren or ibutamoren mesylate, is usually a peptide that belongs to The expansion hormone secretagogues team (GHSR). It works by mimicking the action of your starvation hormone ghrelin. It binds to one of the growth hormone secretagogue receptors (GHSR) from the brain, serving to enha