Objective: To study the influence of Aidi injection on pharmacokinetics of ifosfamide(IFO) in rabbit providing evidence for rational and safe application. Method: The experiment was designed in a randomized cross-over study. The control group was given ifosfamide and NS

and the test group was given ifosfamide and Aidi. Plasma sample was treated with the C18 solid phase extraction column

then concentrationof ifosfamide was determined by HPLC. The pharmacokinetic parameters and bioequiabailability of two groups were analyzed. Result: The main pharmacokinetic parameters of the control group and experimental group were as follows: AUC0-∞ were (140.53±39.26)

(120.02±25.89)mg·L-1·h-1

AUC0-t were (128.37±34.2)

(119.18±25.51) mg·L-1·h-1

Cmax were(158.63±16.35)

(132.61±21.07) mg·L-1. The relative bioabailability of the test group were that F0-∞ was (91.13±34.50)%

F0-t was (97.62±32.59)%. The result of statistical analysis showed that there was no bioequibalence between the control and the test groups and the latter was smaller. Conclusion: The pharmacokinetics of ifosfamide is belong to two compartments model. When ifosfamide and Aidi are administered to the rabbits

the bioavailability of ifosfamide is reduced significantly

which may suggest that the drug metabolism of ifosfamide can be affected significantly. In addition

Aidi injection can decrease the concentration of IFO in rabbits significantly

so the effect of IFO can be attenuated probably.