This study is related to the serious side effects of Doxorubicin-cardiotoxicity and serum lipid caused by the drug's cumulative effect. Studies were performed on experimental animals treated with intensive administration of Doxorubicin. Seventy five wistar rats were divided in two equal groups A and B. Group A was used for doxorubicin administration and B for doxorubicin and dextrazoxane. The drugs were administered weekly for twelve weeks at doses 0.2 mg/100 g BW for doxorubicin and 1.5 mg/100 g BW for dextrazoxane. Histological examination of the cardiac muscle, large vessels, liver and other organs and biochemical examination for serum lipids and liver enzymes were performed on certain weeks. Comparison of the findings of the two groups showed a) a reduction in doxorubicin cardiotoxicity by dextrazoxane and b) the addition of dextrazoxane to doxorubicin resulted in lowering the increase of serum lipids produced by doxorubicin. c) In vitro tests by chemiluminescence showed that dextrazoxane acts as a scavenger of oxygen free radicals.