Introducing the ultimate in pharmaceutical quality supplementation for circulatory and cardiovascular health. New Swanson Ultra AjiPure L-Arginine with L-Citrulline combines pharmaceutical-grade L-arginine from Ajinomoto with Kyowa Quality L-citrulline from Kyowa Hakko. While L-arginine serves as a precursor to nitric oxide, L-citrulline serves as a precursor to L-arginine, extending its benefits. Together, these two ingredients from the world leaders in supplemental aminos deliver top-tier dietary support for healthy circulation and cardiovascular care.