RESUMEN
This study was conducted to compare the bioavailability of two prolonged-release pharmaceutical forms containing 300 mg of diltiazem. The test formulation is a new design of tablets with a hydrophilic matrix, and the reference formulation is capsules containing prolonged liberation microgranules, in the same dose, that are commercially available in the pharmaceutical market. Diltiazem plasma concentrations were analyzed by high-performance liquid chromatography (HPLC), which involves solid-phase extraction for plasma sample preparation. Twelve healthy volunteers participated in the study, which had a single-dose, two-treatment, two-sequence-crossover, randomized design. The preparations were compared using pharmacokinetic parameters such as the area under the plasma concentration-time curve AUC(0-36), peak plasma concentration Cmax, and Cmax/AUC(0-36) ratio as a measure for the absorption rate. No statistically significant difference was observed for any of the parameters, and the 90% confidence intervals calculated for the ratio of the logarithmically transformed AUC(0-36) and Cmax/AUC(0-36) values of both formulations were within the bioequivalence limit of 0.80-1.25. Moreover, an in vitro study of dissolution according to USP 23 was conducted, and the in vitro parameters were calculated.
Asunto(s)
Bloqueadores de los Canales de Calcio/farmacocinética , Diltiazem/farmacocinética , Administración Oral , Adulto , Disponibilidad Biológica , Bloqueadores de los Canales de Calcio/sangre , Cápsulas , Cromatografía Líquida de Alta Presión , Estudios Cruzados , Diltiazem/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Solubilidad , Comprimidos RecubiertosRESUMEN
Theophylline pharmacokinetics, administered in tablets containing 600 mg in a sustained-release hydrophilic matrix for a once daily intake, was evaluated after being administered to 6 healthy volunteers during 7 days at 8 pm. Plasmatic levels at -2, 0, 2, 3, 4, 6, 8, 10, 12, 14, 18 and 24 hours in relation with 8 pm intake, were obtained at the 7th day of administration. A plasmatic curve was obtained with a maximum concentration at 12 hours of 10.18 mcg/ml, a minimum concentration of 3.27 mcg/ml and an area under the concentration/time curve of 198.4 mcg.h/ml. These data make it evident that the tablet studied shows a release profile without excessive peaks and an average concentration at steady state within therapeutical range, and suggests its use in asthma.
Asunto(s)
Teofilina/farmacocinética , Adulto , Femenino , Humanos , Masculino , Valores de Referencia , Comprimidos , Teofilina/administración & dosificación , Teofilina/sangre , Factores de TiempoRESUMEN
Theophylline pharmacokinetics, administered in tablets containing 600 mg in a sustained-release hydrophilic matrix for a once daily intake, was evaluated after being administered to 6 healthy volunteers during 7 days at 8 pm. Plasmatic levels at -2, 0, 2, 3, 4, 6, 8, 10, 12, 14, 18 and 24 hours in relation with 8 pm intake, were obtained at the 7th day of administration. A plasmatic curve was obtained with a maximum concentration at 12 hours of 10.18 mcg/ml, a minimum concentration of 3.27 mcg/ml and an area under the concentration/time curve of 198.4 mcg.h/ml. These data make it evident that the tablet studied shows a release profile without excessive peaks and an average concentration at steady state within therapeutical range, and suggests its use in asthma.
RESUMEN
Theophylline pharmacokinetics, administered in tablets containing 600 mg in a sustained-release hydrophilic matrix for a once daily intake, was evaluated after being administered to 6 healthy volunteers during 7 days at 8 pm. Plasmatic levels at -2, 0, 2, 3, 4, 6, 8, 10, 12, 14, 18 and 24 hours in relation with 8 pm intake, were obtained at the 7th day of administration. A plasmatic curve was obtained with a maximum concentration at 12 hours of 10.18 mcg/ml, a minimum concentration of 3.27 mcg/ml and an area under the concentration/time curve of 198.4 mcg.h/ml. These data make it evident that the tablet studied shows a release profile without excessive peaks and an average concentration at steady state within therapeutical range, and suggests its use in asthma.
RESUMEN
Se administraron 90 mg de diltiazem -en dosis única- vehiculizados en un comprimido de liberación prolongada (diseñado especialmente en base a la utilización de matrices hidrofílicas) a 8 voluntarios sanos, todos del sexo masculino. Se obtuvieron concentraciones plasmáticas de diltiazem cuyo pico máximo se alcanzó a las 6,37 + ou - 0,93 horas con un valor de 82,8 + ou - 11,3 ng/ml. A las 12 horas la concentración plasmática de diltiazem era de 40,2 + ou - 3,9 ng/ml. El t 1/2 fue de 5,77 siendo el área bajo la curva de 1097 + ou - 141 ng/ml x h. Estos datos permiten suponer razonablemente que, con la administración de 1 comprimido (90 mg) de diltiazem -vehiculizado en este nuevo diseño de comprimido de liberación prolongada- cada 12 horas se obtendrán niveles terapéuticos eficaces, minimizando (al mismo tiempo) la probabilidad de aparición de efectos adversos
Asunto(s)
Adulto , Persona de Mediana Edad , Humanos , Masculino , Diltiazem/metabolismo , Disponibilidad Biológica , Ensayos Clínicos como AsuntoRESUMEN
Se administraron 90 mg de diltiazem -en dosis única- vehiculizados en un comprimido de liberación prolongada (diseñado especialmente en base a la utilización de matrices hidrofílicas) a 8 voluntarios sanos, todos del sexo masculino. Se obtuvieron concentraciones plasmáticas de diltiazem cuyo pico máximo se alcanzó a las 6,37 + ou - 0,93 horas con un valor de 82,8 + ou - 11,3 ng/ml. A las 12 horas la concentración plasmática de diltiazem era de 40,2 + ou - 3,9 ng/ml. El t 1/2 fue de 5,77 siendo el área bajo la curva de 1097 + ou - 141 ng/ml x h. Estos datos permiten suponer razonablemente que, con la administración de 1 comprimido (90 mg) de diltiazem -vehiculizado en este nuevo diseño de comprimido de liberación prolongada- cada 12 horas se obtendrán niveles terapéuticos eficaces, minimizando (al mismo tiempo) la probabilidad de aparición de efectos adversos (AU)