Dexrazoxane is used to protect the heart and other tissues from harmful side effects caused by certain cancer medications. The Zinecard brand of dexrazoxane is used in women who are receiving doxorubicin for metastatic breast cancer. The Totect brand of dexrazoxane is used in men or women to treat a condition called extravasation (es-TRA-va-ZAY-shun). Extravasation happens when an injected medicine escapes from the blood vessels and circulates into tissues in the body. Serious tissue damage can occur when extravasation happens during injection of certain cancer medications. Dexrazoxane may also be used for purposes not listed in this medication guide.