Limited information is available describing the pharmacokinetics of hepatically-cleared drugs in burn patients. Based on the hypothesis that after burn injury, plasma meperidine clearance should increase in response to the postburn increase in hepatic blood flow, we examined the kinetics of intravenous meperidine in eleven patients about one week after burn injury (acute study) and in five of these patients about six weeks postburn (convalescent study). The meperidine steady-state distribution volume (about 2 1/kg) during both the acute and the convalescent studies was about half the distribution volume reported in the literature for meperidine in healthy subjects. The meperidine clearance in burn patients (acute, 420 ml/min and convalescent, 600 ml/min) was lower than would be anticipated in the presence of known marked increases in hepatic blood flow in burn patients.