Doxorubicin hydrochloride is a chemotherapeutic agent highly effective against a wide range of neoplasms. A prime limiting factor to the administration of this drug is cardiotoxicity, which frequently develops when the cumulative dose exceeds 500 mg/sq m. Late cardiomyopathy, which may develop up to a year after therapy has been discontinued, was thought to be rapidly progressive and unresponsive to standard cardiac therapy. An adult who received 475 mg/sq m of doxorubicin hydrochloride experienced a cardiotoxic reaction one year after the completion of therapy. The patient responded to standard cardiac therapy. Resolution of left ventricular dysfunction was verified by echocardiography and radionuclide angiocardiography.