OBJECTIVES: Banha-sasim-tang (BST), which consists of seven different herbs, is one of the most popular herbal formulae for treating gastrointestinal disorders in Eastern Asia. The commonly used herbal medicine is often co-administered with other therapeutic drugs, which raises the possibility of herb–drug interactions and may modify the clinical safety profile of therapeutic drugs. METHODS: We investigated the potential herb–drug interactions between BST extract and midazolam (MDZ) in mice. The area under the plasma concentration-time curve (AUC) of MDZ and 1ʹ-hydroxymidazolam (1ʹ-OH-MDZ) was evaluated for both oral and intraperitoneal administration of MDZ, following oral administration of BST (0.5 and 1 g/kg). RESULTS: It was found that the AUC of MDZ and 1ʹ-OH-MDZ was lower in case of oral administration of MDZ. Administration of BST extract was not associated with hepatic cytochrome P450 activity. BST extract induced a strong reduction in pH and it has been reported that oral mucosal absorption of MDZ is lower at low pH. The decreased absorption rate of MDZ might be caused by the ingredients of BST and may not be related to other factors such as increased excretion of MDZ by P-glycoprotein. CONCLUSIONS: The altered pharmacokinetics of midazolam caused by co-administration with BST in vivo could be attributed to a decrease in pH and subsequent reduction of MDZ absorption rate.
Absorption* ; Administration, Oral ; Animals ; Area Under Curve ; Cytochrome P-450 Enzyme System ; Far East ; Herb-Drug Interactions ; Herbal Medicine ; Hydrogen-Ion Concentration* ; Mice ; Midazolam* ; Oral Mucosal Absorption ; P-Glycoprotein ; Pharmacokinetics ; Plasma ; Stomach*

In order to elucidate the physiological basis for mucosal immunity of oral vaccination and to present the essential carrier of microparticles or nanoparticles used to investigate the orally delivered vaccine, the features of antigen presentation and mucosal immunereaction in gut-associated lymphoid tissues were analyzed. Considered the morphological and physiological barriers of the gastrointestinal tract, absorption and transport of particulates were further discussed. And the studies about particulate dosage forms for oral vaccine delivery were also summarized in this review. Peyer s patches and M-cells, involved in immunoregulation, are significant areas performing the critical role in oral vaccine. The applied vesicle of microparticles could overcome the barriers of gastrointestinal tract. Oral vaccination was endued with new connotation, especially the enhanced transport and immunization efficiencies promoted by the lectin anchored particles. In conclusion, oral vaccination mediated by particulate carrier via mucosal immune system, would contribute to the site-specific triggering and signal magnification. For vaccines, the prospects for the application of these promising carrier systems might have potential attraction for scientific research and commercial development.
Administration, Oral ; Animals ; Drug Delivery Systems ; methods ; Humans ; Immunity, Mucosal ; Intestinal Absorption ; Microspheres ; Nanoparticles ; Vaccination ; methods ; Vaccines ; administration & dosage ; immunology ; pharmacokinetics