Penicillamine: an anti-rheumatoid drug.

Penicillamine is now established as a useful disease remittive drug in the treatment of rheumatoid arthritis. Improvement during a successful course of treatment may be found in a decrease in the degree of synovitis, which is associated with a reduction in the level of rheumatoid factor and immune complexes in serum and synovial fluid. Vasculitic lesions also resolve. There is roentgenographic evidence of healing of the erosive lesions after two to three years of treatment. The multiplicity of adverse effects caused by the drug limits its usefulness, although with increasing experience more patients are being treated successfully. The induction of autoimmune side effects in a small number of patients treated with penicillamine has elicited particular interest since this may represent a clue to its mechanism of action on the immune system. The over-all approach to the use of the drug, including currently accepted methods of dosing and safety monitoring, is reviewed.