Used primarily in the treatment of Wilson's disease, it helps remove excess copper from the body by forming a complex that is excreted in urine. It is also employed in cases of cystinuria to reduce the formation of cystine stones by forming a more soluble compound with cystine. Additionally, it has applications in rheumatoid arthritis to reduce inflammation and joint damage, though its use in this condition has declined with the advent of newer therapies. It serves as a chelating agent for heavy metal poisoning, such as lead or mercury, by binding and facilitating their excretion. The disulfide form is often utilized for its stability and controlled release properties in pharmaceutical formulations.