The metabolic clearance rates of ketone bodies were determined in anesthetized dogs following the intravenous administration of either Escherichia coli endotoxin or saline, in order to examine the influence of endotoxin on the efficiency of peripheral ketone body removal. A nonisotopic method was employed for these studies consisting of a stepwise infusion of beta-hydroxybutyrate at three different rates. At each infusion rate, a steady-state arterial concentration was reached, at which time the rate of appearance of ketone bodies equaled their removal rates. Rates of infusion were plotted against the steady-state arterial concentrations, and the reciprocal of the slope of this linear relationship represented the metabolic clearance rate. Administration of endotoxin did not alter the metabolic clearance rate of ketone bodies. The uptake of ketone bodies by the thigh muscles was also unaffected by endotoxin administration. It is concluded, that E. coli endotoxin does not influence the efficiency of peripheral ketone body removal.