This study was carried out in the Wistar rats to investigate the effect of Tang herb on the pharmacokinetics of the antiretroviral drug lopinavir （LPV） following single oral administration. Rats were randomly divided into LPV group （36 mg/kg） and LPV combining with Tang herb group （LPV： 36 mg/kg, Tang herb： 864 mg/kg）. The blood concentrations of lopinavir at 0, 0.5, 1, 2, 4, 8, 10, 12, 14, 16, 22 h after administration were determined by HPLC and the pharmacokinetic parameters were investigated. The results showed that Tang herb significantly increased the Cmax and A UC （P〈0.05） while slightly increased the t1/2z and Tmax of lopinavir （P〉0.05）. The present study suggests that Tang herb may delay the absorption, increase the time to reach the maximum concentration, and improve the bioavailability of LPV. Further evaluation of the possible interaction mechanism between Tang herb and LPV needs to be studied.
