The active ingredient in a drug used to treat severe side effects caused by certain anticancer drugs. It is used to treat the toxic effects of an anticancer drug that leaks from a vein into surrounding tissue and causes tissue damage. Dexrazoxane is also used to reduce heart damage in women given doxorubicin for breast cancer that has spread to other parts of the body. It is also being studied in the treatment of some types of cancer. Dexrazoxane is a type of cardioprotective agent, a type of chemoprotective agent, and a type of topoisomerase inhibitor.