Doxorubicin concentration time course in the myocardium after single administration to the dog. Possible role in the cardiac effects.

Three hours after i.v. administration of doxorubicin, concentrations of the drug in the myocardium are much higher (about 50 times) and decrease much more slowly (drug still detected 21 days later) than those in the plasma, so that storage results from too early readministration, with possible toxic signs.