Energy and Cardiovascular Support500 mg Per CapsuleDietary SupplementSupports Sports PerformancePairs With Methionine and Glycine to Aid the Making of Energy in Your MusclesSupports Blood Pressure Already Within a Normal RangeScience-Backed Quality Since 1969Get fundamental amino acid nutrition for less with Swanson L-Arginine. Our L-arginine makes an economical and effective addition to your dietary plan, especially if you are interested in supporting cardiovascular and immune system health. Each convenient capsule delivers 500 mg of free-form L-arginine.