Objective: To study the pharmacokinetics of rhein in 12 healthy volunteers after oral administration of rhubarb extract.
Method: The blood sample were obtained at 0,0.083,0.5,1,1.5,2,3,4,5,7,10 h after a single dose oral administration of rhubarb (50 mg x kg(-1)). The plasma rhein concentration was determined by HPLC. The pharmacokinetics of rhein were analysed by 3P97 program.
Result: The absorption of rhein was very fastafter oral administration of rhubarb extract in the healthy volunteers. The main pharmacokinetic parameters of rhein were C(max) (3.20 +/- 1.08) microg x mL(-1); t(max) (1.03 +/- 0.41) h; t(1/2alpha) (0.21 +/- 0.02) h; t(1/2beta) (2.68 +/- 1.09) h; MRT(5.31 +/- 1.78) h; AUC(0-infinity) (1 573.08 +/- 366.48) microg x mL(-1) min(-1), respectively.
Conclusion: Rhein could be absorbed rapidly and its pharmacokinetics was consistent with two-compartment model.