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Cimetidina: interacción con anticoagulantes orales en el hombre
Lancet (London, England)
|August 18, 1979
Resumen
La cimetidina prolonga significativamente el tiempo de protrombina (PT) en pacientes que toman anticoagulantes orales como la warfarina. Esta interacción farmacológica, probablemente debido a la inhibición del metabolismo, requiere precaución durante el tratamiento simultáneo.
Área de la Ciencia:
- Farmacología Farmacología.
- Interacciones farmacológicas Interacciones farmacológicas
- La medicina clínica es la medicina clínica.
Sus antecedentes:
- Los anticoagulantes orales (por ejemplo, la warfarina) son cruciales para prevenir los eventos tromboembólicos.
- La cimetidina es un medicamento de uso común para el reflujo ácido y las úlceras.
- Las posibles interacciones farmacológicas requieren una investigación exhaustiva para garantizar la seguridad del paciente.
Objetivo del estudio:
- Para investigar la interacción entre la cimetidina y la terapia anticoagulante oral.
- Para cuantificar el efecto de la cimetidina en el tiempo de protrombina (PT) y los niveles de warfarina.
- Para dilucidar el mecanismo farmacocinético subyacente a esta interacción farmacológica.
Principales métodos:
- Estudio realizado en 6 pacientes que tomaban anticoagulantes orales y 7 voluntarios sanos.
- Se midió el tiempo de protrombina (PT) y las concentraciones plasmáticas de warfarina.
- El aclaramiento del fármaco de la warfarina y la antipirina se evaluó en presencia de cimetidina.
Principales resultados:
- La adición de cimetidina prolongó la PT en una media de 12.6 segundos en los pacientes.
- En los voluntarios, la cimetidina aumentó la TP de 19,4 a 22,9 segundos.
- La concentración plasmática de warfarina aumentó de 0,96 a 1,76 microgramos/ml; el aclaramiento del fármaco disminuyó.
Conclusiones:
- La cimetidina potencia significativamente el efecto anticoagulante de los anticoagulantes orales.
- La interacción es probablemente mediada por la inhibición de la cimetidina del metabolismo de los fármacos.
- Se recomienda precaución al administrar cimetidina junto con anticoagulantes orales.
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