Corpus ID: 44536205

Effect of low dose quinidine on encainide pharmacokinetics and pharmacodynamics. Influence of genetic polymorphism.

  title={Effect of low dose quinidine on encainide pharmacokinetics and pharmacodynamics. Influence of genetic polymorphism.},
  author={C. Funck-Brentano and J. Turgeon and R. Woosley and D. Roden},
  journal={The Journal of pharmacology and experimental therapeutics},
  volume={249 1},
Encainide biotransformation to its active metabolites O-desmethyl encainide and 3-methoxy-O-desmethyl encainide cosegregates with the polymorphic oxidation of debrisoquine. Because quinidine has been reported recently to be a potent inhibitor of the enzyme responsible for this polymorphism (cytochrome P450db1), we tested the hypothesis that quinidine would selectively inhibit encainide metabolism and alter its effects in subjects with the extensive metabolism phenotype for debrisoquine… Expand
The effect of diltiazem on the disposition of encainide and its active metabolites
Diltiazem inhibited the first‐pass metabolism of encainide, resulting in increased bioavailability, which appeared to be caused by the inhibition of debrisoquin 4‐hydroxylase and impairment of other unmeasured metabolic pathways forencainide. Expand
Stereoselective genetically-determined interaction between chronic flecainide and quinidine in patients with arrhythmias.
The effects of adding low dose quinidine, a potent inhibitor of P450IID6, to chronic flecainide therapy in patients with arrhythmias were evaluated and it was found that in extensive metabolizer patients receiving chronic fle cainide, increased plasma concentrations will develop if P450 IID6 is inhibited. Expand
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Clinicians should be alert to unusual drug reactions in patients receiving quinidine concurrently with the other medications because no test is commonly available to determine directly the debrisoquin metabolic phenotype. Expand
Impact of P450 genetic polymorphism on the first-pass extraction of cardiovascular and neuroactive drugs.
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Effects of encainide and metabolizer phenotype on ventricular conduction during exercise.
If rate-dependent intraventricular conduction slowing could be demonstrated in patients receiving encainide during exercise-induced sinus tachycardia is determined, and this effect is related to the genetic phenotype ofencainide metabolism. Expand
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