Arginine and Ornithine combines two complementary amino acids in one convenient supplement. Arginine is required for proper elimination of urea from the body, which occurs through a critical metabolic cycle that detoxifies the body of nitrogen compounds that are normal byproducts of protein metabolism. Ornithine is synthesized from Arginine and is a precursor of citrulline, proline and glutamic acid. Both of these amino acids are popular with athletes and other active individuals. Natural color variation may occur in this product.