The persistence of adriamycin in man and rat.

1 Adriamycin was administered as a single intravenous dose. The plasma concentration in man and rat decayed as a double exponential function of time. 2 A two compartment model was used to predict plasma and tissue concentrations in man and the rat. The validity of the tissue concentration predictions was confirmed experimentally in the rat. 3 Tissue components had a high capacity for the drug. There was evidence in the rat of preferential accumulation in the liver, spleen and bone marrow. 4 The large tissue capacity and the prolonged half time for elimination predispose to accumulation. This may be responsible for the greater toxicity of treatment schedules with short intervals between consecutive doses.