After a single oral dose of ATV with or without DXM, the plasma concentrations of ATV, o- ATV, and p- ATV at each time point were determined, as presented in Figure 2. Meanwhile, the pharmacokinetic parameters of ATV, o- ATV, and p- ATV are presented in Table 6. Herein, DXM increased the plasma exposure of ATV substantially. Compared with ATV alone, the C_max (peak plasma concentration) of ATV was increased by 0.388 times with DXM, and the AUC_(0-t) and AUC_(0-∞) were increased by 1.156 times (P < 0.05) and 1.550 times (P< 0.05), respectively. Moreover, the AUC_(0-t)and AUC_(0-∞) values of the two active metaboliteso- ATV and p- ATV were increased with DXM, although there were no statistical differences found in the C_maxvalues, which were only slightly increased by 0.313 times and 0.106 times, respectively. AUC_(0-t) and AUC_(0-∞) of o- ATV were increased by 1.320 times (P < 0.05) and 1.420 times (P < 0.05), respectively. Furthermore, the corresponding values for p- ATV were increased by 1.209 times (P < 0.05) and 1.676 times (P < 0.05), respectively. The t_max (time to peak plasma concentration) remained statistically unaltered by DXM, for atorvastatin and its active metabolites. DXM lengthened the t_1⁄2 (elimination half-life) of ATV, o- ATV, and p- ATV by 1.304 times (P < 0.05), 1.196 times (P < 0.05), and 1.457 times (P < 0.05), respectively.