Pharmacokinetics of thiopentone in a group of young women and a group of young men.

The average induction dose of thiopentone did not differ significantly when eight young women were compared with eight young men. In neither group did the dose increase with increased body weight. Clearance of thiopentone from venous blood was described by a three-compartment open model. The average volumes of V1 and V3 were greater in the females, but only the difference between the V3 values was significant (P < 0.05). Significant correlations (P < 0.01) were found between the initial drug concentrations and the k12 values. The slopes of the regression lines were 0.0029 for the women and 0.0038 for the men (0.1 < P < 0.2). It is suggested that the redistribution rate constant k12 is predominant in determining the sleep dose rather than the initial distribution volume V1.