RESUMEN
PURPOSE: The objective of the study was to evaluate the synergistic transdermal permeation effect of chemical enhancers and iontophoresis technique on tolterodine tartrate (TT) transdermal gel and to evaluate its pharmacokinetic properties. MATERIALS AND METHODS: Taguchi robust design was used for optimization of formulations. Skin permeation rates were evaluated using the Keshary-chein type diffusion cells in order to optimize the gel formulation. In-vivo studies of the optimized formulation were performed in a rabbit model and histopathology studies of optimized formulation were performed on rats. RESULTS: Transdermal gels were formulated successfully using Taguchi robust design method. The type of penetration enhancer, concentration of penetration enhancer, current density and pulse on/off ratio were chosen as independent variables. Type of penetration enhancer was found to be the significant factor for all the responses. Permeation parameters were evaluated when maximum cumulative amount permeated in 24 hours (Q24) was 145.71 ± 2.00µg/cm² by CIT4 formulation over control (91.89 ± 2.30µg/cm²). Permeation was enhanced by 1.75 fold by CIT4 formulation. Formulation CIT4 containing nerolidol (5%) and iontophoretic variables applied (0.5mA/cm² and pulse on/off ratio 3:1) was optimized. In vivo studies with optimized formulation CIT4 showed increase in AUC and T1/2 when compared to oral suspension in rabbits. The histological studies showed changes in dermis indicating the effect of penetration enhancers and as iontophoresis was continued only for two cycles in periodic fashion so it did not cause any skin damage observed in the slides. CONCLUSION: Results indicated that iontophoresis in combination with chemical enhancers is an effective method for transdermal administration of TT in the treatment of overactive bladder.
Asunto(s)
Compuestos de Bencidrilo/farmacocinética , Cresoles/farmacocinética , Iontoforesis/métodos , Fenilpropanolamina/farmacocinética , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Agentes Urológicos/farmacocinética , Administración Cutánea , Animales , Compuestos de Bencidrilo/administración & dosificación , Compuestos de Bencidrilo/sangre , Cresoles/administración & dosificación , Cresoles/sangre , Sinergismo Farmacológico , Geles , Masculino , Modelos Animales , Fenilpropanolamina/administración & dosificación , Fenilpropanolamina/sangre , Conejos , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Absorción Cutánea , Factores de Tiempo , Tartrato de Tolterodina , Resultado del Tratamiento , Agentes Urológicos/administración & dosificación , Agentes Urológicos/sangreRESUMEN
Purpose The objective of the study was to evaluate the synergistic transdermal permeation effect of chemical enhancers and iontophoresis technique on tolterodine tartrate (TT) transdermal gel and to evaluate its pharmacokinetic properties. Materials and Methods Taguchi robust design was used for optimization of formulations. Skin permeation rates were evaluated using the Keshary-chein type diffusion cells in order to optimize the gel formulation. In-vivo studies of the optimized formulation were performed in a rabbit model and histopathology studies of optimized formulation were performed on rats. Results Transdermal gels were formulated successfully using Taguchi robust design method. The type of penetration enhancer, concentration of penetration enhancer, current density and pulse on/off ratio were chosen as independent variables. Type of penetration enhancer was found to be the significant factor for all the responses. Permeation parameters were evaluated when maximum cumulative amount permeated in 24 hours (Q24) was 145.71 ± 2.00µg/cm2 by CIT4 formulation over control (91.89 ± 2.30µg/cm2). Permeation was enhanced by 1.75 fold by CIT4 formulation. Formulation CIT4 containing nerolidol (5%) and iontophoretic variables applied (0.5mA/cm2 and pulse on/off ratio 3:1) was optimized. In vivo studies with optimized formulation CIT4 showed increase in AUC and T1/2 when compared to oral suspension in rabbits. The histological studies showed changes in dermis indicating the effect of penetration enhancers and as iontophoresis was continued only for two cycles in periodic fashion so it did not cause any skin damage observed in the slides. Conclusion Results indicated that iontophoresis in combination with chemical enhancers is an effective method for transdermal administration of TT in the treatment of overactive bladder. .
Asunto(s)
Animales , Masculino , Conejos , Ratas , Compuestos de Bencidrilo/farmacocinética , Cresoles/farmacocinética , Iontoforesis/métodos , Fenilpropanolamina/farmacocinética , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Agentes Urológicos/farmacocinética , Administración Cutánea , Compuestos de Bencidrilo/administración & dosificación , Compuestos de Bencidrilo/sangre , Cresoles/administración & dosificación , Cresoles/sangre , Sinergismo Farmacológico , Geles , Modelos Animales , Fenilpropanolamina/administración & dosificación , Fenilpropanolamina/sangre , Ratas Wistar , Reproducibilidad de los Resultados , Absorción Cutánea , Factores de Tiempo , Resultado del Tratamiento , Agentes Urológicos/administración & dosificación , Agentes Urológicos/sangreRESUMEN
Root canals of 21 maxillary human teeth were enlarged with reamers and flushed alternatively with sodium hypochlorite and hydrogen peroxide. After its mechanical preparation, root canals were dressed with camphorated paramonochloropherol and/or formocresol delivered by paper points. All three medicaments crystallize both on dentin walls and inside dentinal tubules. The clinical implications of these findings are discussed.