Dose-dependent pharmacokinetics of tyrosol galactoside as an anti-fatigue drug in rats.

Tyrosol galactoside (TG) is a new candidate anti-fatigue agent under development. In order to have a good understanding of its pharmacokinetic characters, the paper describes the dose-dependent pharmacokinetics of TG in rats after oral and intravenous administration. TG was rapidly absorbed after oral administration and cleared with first-order rate, for the plasma half-life was independent of dose. C(max) and AUC(0-infinity) after both intravenous and oral dosing were all linearly correlated with the dose, as the regression correlation coefficient (R) was 0.998, 0.989 and 0.994 for AUC(0-infinity) (i.v., P < 0.01) AUC(0-infinity) (i.g., P < 0.01) and C(max) (i. g., P < 0.01), respectively. However, these parameters increased less than proportionally with increasing dose. In addition, the apparent volume of distribution (Vd) and the apparent clearance (Cl) seemed to be affected by the dose.