Pharmacodynamic variability of flecainide assessed by QRS changes

@article{Padrini1993PharmacodynamicVO,
  title={Pharmacodynamic variability of flecainide assessed by QRS changes},
  author={Roberto Padrini and Donatella Piovan and M. Busa and Muhamad AL‐BUNNI and Piera Maiolino and Mariano Ferrari},
  journal={Clinical Pharmacology \& Therapeutics},
  year={1993},
  volume={53}
}
The effect of flecainide on the QRS interval was studied in 10 patients who were receiving long‐term oral treatment (50 to 150 mg twice daily) for arrhythmias that were refractory to other drugs. Total and free drug plasma levels and QRS durations were measured at intervals after the morning administration. Free drug plasma levels were linearly correlated with QRS duration in each patient and the slope of the line was widely variable in the population studied. Even after the data from one… 

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