Cysteine hydrochloride, penicillamine for rheumatoid arthritis, autoimmune chronic active hepatitis disease, scleroderma, Sjogren, arthritis syndrome, showing a significant effect. Rheumatoid arthritis, reduce joint pain, swelling and exudate, early morning joint stiffness, erythrocyte sedimentation rate, clinical symptoms improved significantly, which normally takes several weeks before markedly premature withdrawal easy to relapse. Enables patients with chronic active hepatitis or transaminase decreased to normal. For the treatment of scleroderma, skin collagen cross-linking can reduce the tension increased.

Homocysteine is converted by the body into methionine; and this process must have vitamin B6 participation. Homocysteine may help eliminate toxic substances in order to protect the cells, as a member of the best free radical destroyer, when taken together with selenium and vitamin E, cysteine to maximize skill. In addition to protecting cells from harmful effects of radiation, and also protect the liver from alcohol and tobacco harm the brain. Treatment of rheumatoid arthritis, may wish to add some cysteine, which has chelate, the body of excess copper discharge. Also promote fat burning and build muscle.
Non-essential amino acids and is a polar molecule, containing S atom, pKa value of about 9.0, is a strong nucleophile will and acetaldehyde, acyl class of drug reactions and alkanes, this is an important feature of enzymes. Its and zinc, iron, copper and mercury and other metal ions are involved in many important biochemical reactions. Its presence will destroy the protein α-helix of hydrogen bonds, derivatives include: coenzyme A (CoA), α- keratin (α-keratin) and grains glutathione (glutathione By oxidation of a disulfide bond to provide a much more stable extracellular proteins, the reaction in some cases certain Hing reversible, so in the laboratory, many proteins will require antioxidant or anti electrophilic protected to preserve functionally active. In biochemical reactions cysteine residues are acylated. Cysteine residues may be involved in heme repair. Can be produced by β-elimination dehydrogenation Ala in an alkaline environment, and further generates amine acid lanthionine and other products (lanthionine, lysinoalanine) to form a wool protein.