L-Arginine Hydrochloride is one of the 20 amino acids that build up protein. L-arginine is one of the non-essential amino acids, meaning it can be synthesised in the body.L-arginine HCL is a precursor of nitric oxide and other metabolites. It is an important component of collagen, enzymes and hormones, skin and connective tissues. L-arginine plays important roles in the synthesis of various protein molecules; creatine and insulin being the most easily recognised. It may have antioxidant property and reduces accumulation of compounds such as ammonia and plasma lactate, by-products of physical exercise. It also inhibits platelet aggregation and has also been known to decrease blood pressure.