Disposition kinetics of ropivacaine in humans

The pharmacokinetic characteristics of a new local anesthetic drug, ropivacaine, were determined after intravenous infusion of 50 mg of the hydrochloride salt into six healthy male volunteers. Results showed that the disposition of ropivacaine can be described by a biexponential function. Its blood clearance (0.72 +/- 0.16 L/min) is intermediate between that of mepivacaine and bupivacaine. Plasma binding averaged 94% +/- 1% and the volume of distribution at steady state based on blood drug concentration was 59 +/- 7 L. The terminal elimination half-life was 111 +/- 62 min.