The present study reports findings on the disposition of epirubicin after an intrahepato-arterial administration of the Lipiodol-drug complex, prepared by mixing the drug-aqueous phase with the iodized oil by ultra-sonification, in 14 patients with histologically proven hepatoma or hepatomegaly with serum alpha-fetoprotein level above 500 micrograms.l-1. The volume of Lipiodol used was 5 ml and the epirubicin dose was 50 mg.m-2. Blood samples were obtained at various time intervals up to 72 h post-dose. Serum concentrations of epirubicin were measured by liquid chromatography with fluorometric detection. The area under serum concentration-time curve (AUCinfinity0) was higher in the Lipiodol-epirubicin group (n = 8) while the clearance was faster and elimination t1/2 and mean residence time shorter in the plain epirubicin group (n = 3). However, interindividual variation in metabolism of epirubicin would affect serum level of the drug. In three patients who were given intravenous and intrahepato-arterial injections (90 mg.m-2) of plain epirubicin and Lipiodol-drug complex, the relative bioavailability of Lipiodol-epirubicin complex (F = 0.76 and 0.45) was lower than that of plain epirubicin (F = 0.80 and 0.73) in two patients while it was approximately 100% (F = 1.06 and 1.20) in one patient. It is likely that liver function of the patients might be modified by the disease state over a period of 3 months in the cross-over study. Further studies with larger patient samples are required to confirm if there is a targeting effect of the Lipiodol-drug complex toward hepatoma using a better formulation of the drug in Lipiodol.