Cysteine hydrochloride is soluble in water and can be quickly absorbed by human body when it is made into injection or tablet. It is the main raw material for the production of carboxymethyl cysteine and acetylcysteine; It is bread improver; Nutritional supplements, antioxidants, color protectants. It has the function of detoxification, prevention of radiation injury, treatment of tracheitis and expectoration.