In vivo Studies of the Effect of a Herbal Preparation on Pharmacokinetic Properties of Rifampicin in Male Swiss Albino Rats and Computer Mediated Mechanism of Interaction

This study investigates the effect of aherbal preparation (‘Goko’ Cleanser), on the pharmacokinetic profile of orally administered Rifampicin in Swiss albino male rats. The In vivo study was carried out in three phases. In phase I only Rifampicin (20mg/kg body) was orally administered to ratsand in phase II, Rifampicin and Goko Cleanser (30ml/kg body weight) were concurrently administered and in phase III Goko Cleanser was administered for 6 days before Rifampicin. Blood samples were collected from rats in each group at 0, 1, 2, 3, 6, 9 and 12 hours in each phase and concentration determined by spectrophotometric method. Pharmacokinetics parameters determined include, Cmax, Tmax, t1/2α, ClT, AUC0-9, AUC0-∞, t1/2β and kβ. The In-silico studies was done by docking molecules contained in the herbal cleanser into rifampicin binding site on the Pregnane X receptor (PXR). The result showed Rifampicin pharmacokinetics profile to be in line with previous reports. Goko Cleanser significantly (P0.05, 00.01) increase the Cmax, Tmax, AUC0-9, AUC0-∞, and t1/2Î²ï€ but decrease ClT, when administer concurrently with Rifampicin (Phase II). Goko Cleanser significantly (P0.05) decrease the Cmax, Tmax, t1/2α, AUC0-9, AUC0-∞, and t1/2β but increase ClT when Rifampicin was administered after 6 days of taking Goko Cleanser (Phase III). In silico docking results showed a significant interaction of Goko Cleanser constituents with active site binding residues and complex formation between constituents of Goko cleanser and rifampicin when administered together. Taking Goko cleanser with rifampicin at the same or within a week should be avoided..