L Arginine and L carnitine Arginine is an amino acid which we can also produce naturally . This increases your notice oxide production , human growth hormone and improves circulation. These three Colorado State University Pueblo CSU Pueblo Injectable Peptides vs Neurotoxins Raleigh NC L Arginine Caps, 700 mg, 200 vegetarian capsules Life Extension Rexdrive Amino with L Arginine HCl, L Citrulline, Acetyl L Carnitine Arginate DiHydrochloride, and Glycine L Carnitine Injection Levocarnitine IV