The effect of quinidine and other oral antiarrhythmic drugs on serum digoxin. A prospective study.

@article{Leahey1980TheEO,
  title={The effect of quinidine and other oral antiarrhythmic drugs on serum digoxin. A prospective study.},
  author={Edward B. Leahey and James A. Reiffel and E G Giardina and John Thomas Bigger},
  journal={Annals of internal medicine},
  year={1980},
  volume={92 5},
  pages={
          605-8
        }
}
We compared the effects of quinidine and three alternate antiarrhythmic drugs on serum digoxin concentration in 63 patients before and during administration of quinidine, procainamide, disopyramide, or mexiletine. Quinidine increased digoxin concentration by at least 0.5 nmol/L in 21 of 22 patients: Mean serum digoxin rose from 1.2 nmol/L to 2.4 nmol/L (P less than 0.001). Procainamide, disopyramide, or mexiletine increased serum digoxin by 0.5 nmol/L in one of 41 patients. Anorexia, nausea… 
Quinidine-digoxin interaction: Evidence for involvement of an extrarenal mechanism
TLDR
The increase in SDC in anuric patients indicates a decrease in the extrarenal clearance of digoxin, which means that mechanisms other than of renal origin are also involved in the interaction of quinidine and digoxin.
Digitoxin elimination reduced during quinidine therapy.
TLDR
The data suggest that the mechanism for this interaction between quinidine and digitoxin is a reduction in elimination and not displacement of digitoxin from tissue binding sites.
Interaction between 16-acetyl-gitoxin and drugs
TLDR
In 6 healthy volunteers and 11 patients suffering from congestive heart failure and rhythmic disturbances, the effects of combined pengitoxin/quinidine administration were studied and interactions between glycoside and cholestyramine or almasilate, an aluminium-magnesium trisilicate, were examined.
An Electrophysiologic Study of the Digoxin—Quinidine Interaction
TLDR
Changes induced by the drug combination appeared to be the sum of changes induced by each drug alone, rather than the total of changes inducing by eachdrug alone.
Digoxin — Quinidine Interaction
  • T. Cheng
  • Medicine
    Journal of the American Geriatrics Society
  • 1982
TLDR
This omission is unfortunate, not only because patients with atrial fibrillation, which was one of the two disorders evaluated by the authors for digoxin therapy, frequently receive quinidine, but because of the high prevalence of interactions betweenQuinidine and digoxin, which is now well recognized.
Quinidine and Digoxin
TLDR
It is prudent to monitor serum digoxin concentrations during concomitant quinidine treatment and to adjust the digoxin dose according to the results, when the toxicity is severe or dose adjustment is difficult.
On the interaction between phenytoin and digoxin
  • H. Rameis
  • Medicine, Biology
    European Journal of Clinical Pharmacology
  • 2004
TLDR
The data suggest that with this drug combination the serum digoxin concentration should be carefully monitored and, if necessary, the daily digoxin dose should be increased.
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