Citrulline is a non-essential amino acid that is an important intermediate in the urea cycle, functioning along with Arginine and Ornithine to rid the body of ammonia, a byproduct of protein metabolism. Because Citrulline is a precursor of Arginine, it provides a readily available source material for Arginine production, which in turn, can be used for the production of Nitric Oxide (NO). NO plays a fundamental role in vascular function and blood flow. Citrulline therefore, not only supports detoxification pathways, but also supports NO production and a healthy cardiovascular system. Supplement Facts: Serving Size: 2 CapsulesServings Per Container: 45 Amount Per Serving: L-Citrulline 1.5 g (1,500 mg) Other Ingredients: Gelatin (capsule), Calcium Carbonate, Magnesium Oxide and Magnesium Stearate (vegetable source).