Juvenile swine were given cocaine at doses which resulted in seizures and wide complex tachycardia. Five minutes after administration, animals were euthanized; blood samples were taken at time of death and 8 hours later and analyzed for presence of cocaine, benzoyl ecgonine (BE) and ecgonine methyl ester (EME) using gas chromatography/mass spectrometry. There were no significant increases over time in mean femoral vein concentrations of cocaine or BE, however mean EME concentrations increased significantly over the 8 hours. Eight-hour postmortem VH cocaine concentrations increased in all animals and were similar to femoral vein concentrations at time of death. There was a large interanimal variability in direction and magnitude of concentration changes. The results highlight to need to consider time and site of blood sample collection when interpreting postmortem cocaine and metabolite concentrations relative to premortem values. 2 tables, 3 figures, and 26 references