**1. Introduction**

This chapter gives the state of the art on doxorubicin (DOX) toxicity in mitochondria, particularly heart tissue. It is well known that cancer is a global threat to human health. The therapeutic effect of the drug is still below expectations in satisfaction. The drug that is the subject of the current chapter is a good chemotherapeutic against various soft solid cancer types. However, its toxic effect on noncancerous tissue, especially heart tissue, has not been ruled out. Therefore, even cancer patient can accomplish to fight cancer; they

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

have still kept going to fight various severe diseases related to chemotherapeutic agents. The clinic utilization of drug is limited due to its side effects. When the molecular mechanism of the chemotherapeutic drug's side effects is clarified, it will be possible to manage all side effects. Hopefully, DOX may be able to improve the lifespan of cancer patients, which is why the purpose of the present chapter is to summarize its toxic effects on cardiac mitochondria.
