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Tolerancia al dinitrato de isosorbido: tasa de desarrollo y reversión
Circulation
|November 1, 1983
Resumen
La tolerancia al dinitrato de isosorbida (ISDN) en pacientes con angina de pecho implica una disminución de la respuesta circulatoria, no una reducción de la absorción del medicamento. El restablecimiento de la respuesta sugiere que la tolerancia es reversible y puede implicar metabolitos ISDN.
Área de la Ciencia:
- Cardiología Cardiología.
- Farmacología Farmacología.
Sus antecedentes:
- La angina estable crónica requiere un manejo eficaz de las respuestas circulatorias.
- El dinitrato de isosorburo (ISDN) es un medicamento antianginal común.
- La tolerancia a ISDN puede limitar su eficacia a largo plazo.
Objetivo del estudio:
- Para investigar la respuesta circulatoria y las concentraciones plasmáticas de dinitrato de isosorbida (ISDN) en pacientes con angina crónica estable.
- Evaluar el desarrollo y la reversibilidad de la tolerancia a ISDN.
- Para explorar los mecanismos potenciales que subyacen a la tolerancia ISDN.
Principales métodos:
- 10 pacientes con angina estable recibieron ISDN sublingual.
- La terapia ISDN oral (15 mg cada 6 horas) se administró durante 48 horas.
- Las respuestas circulatorias y los niveles plasmáticos de ISDN se midieron durante las fases de control, tolerancia y retirada.
- Se utilizó la sustitución con placebo para evaluar la reversibilidad.
Principales resultados:
- La ISDN sublingual causó inicialmente reducciones significativas en la presión arterial.
- Después de 48 horas de ISDN oral, la respuesta vasodepresora disminuyó significativamente, lo que indica tolerancia.
- La tolerancia se resolvió dentro de las 21 horas después de cambiar a placebo.
- Las concentraciones plasmáticas de ISDN no se redujeron en el estado tolerante, lo que sugiere que la biodisponibilidad no es la causa.
Conclusiones:
- La tolerancia al isosorbido dinitrato en pacientes con angina de pecho se caracteriza por una respuesta circulatoria atenuada.
- Es probable que la tolerancia no se deba a una disminución de la biodisponibilidad del fármaco o a una eliminación acelerada.
- La acumulación de metabolitos ISDN puede contribuir a la tolerancia.
- La reversibilidad de la tolerancia sugiere la posibilidad de ajustes terapéuticos.
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