Pharmacokinetics of succinylcholine in man.

The pharmacokinetics of succinylcholine (SCh) 1 or 2 mg/kg was studied in 14 anesthetized patients. Arterial blood concentrations of SCh were measured using a high-performance liquid chromatographic assay. The arterial concentration vs. time data were analyzed by log-linear regression and fitted to an one-compartment model. The pharmacokinetic parameters were (SCh 1, n = 8 and 2 mg/kg, n = 6): apparent volume of distribution (16.4 +/- 14.7 and 5.6 +/- 6.8 ml/kg, mean +/- S.D.), total body clearance (40.5 +/- 38.7 and 15.0 +/- 14.8 liter/min), area under the plasma concentration-time curve (124.3 +/- 163.2 and 695.3 +/- 1008.9 min.micrograms/ml), and elimination half-life (16.6 +/- 4.8 and 11.7 +/- 4.5 sec). The rapid disappearance of SCh from the blood may be due to diffusion out of the blood vessel.