In vivo pharmacokinetics comparisons of icariin, emodin and psoralen from Gan-kang granules and extracts of Herba Epimedii, Nepal dock root, Ficus hirta yahl

Gan-kang granules (GKG) contains the extracts from eight Chinese herbs and is a traditional Chinese composite prescription for treatment of hepatitis B. Icariin, emodin and psoralen are main effective ingredients of the medicine. In this research, pharmacokinetic comparisons of icariin, emodin and psoralen from the extracts of Herba Epimedii, Nepal dock root and Ficus hirta yahl, and GKG were conducted. At different time points (0.25, 0.5, 0.75, 1, 1.5, 2, 4, 6, 8, 12 and 24 h) after administration, the concentrations of icariin, emodin and psoralen in rat plasma were determined by HPLC-UV, and main pharmacokinetic parameters were estimated. The pharmacokinetic parameters of icariin, emodin and psoralen in GKG were elevated comparing with those of herb extracts. Three HPLC-UV methods were developed successfully for the analysis of icariin, emodin and psoralen in SD rat plasma. Some ingredients in GKG may increase the dissolution and absorption, and improve bioavailability of icariin, emodin and psoralen in rats.