Ibutamoren is a synthetic nonpeptide compound, referred to as a ghrelin mimetic, that activates L-type calcium channels, which leads to intracellular calcium increases and activation of protein kinase C (an enzyme that controls the function of various proteins). Ibutamoren interacts with growth hormone-releasing hormone (GHRH) and stimulates the release of growth hormone and insulin-like growth factor-1 (IGF-1). This can increase hunger and also reduce nitrogen wasting during energy restriction. Nitrogen wasting occurs when proteins (e.g., in muscles) are broken down into amino acids for energy and then removed from the body usually via urine.[1] Reduced nitrogen wasting is thought to be how ibutamoren increases fat-free mass.