Warfarin sodium interaction

O Reilly, R. A., Studies on the coumarin anticoagulant drugs interaction of human plasma albumin and warfarin sodium. J. Clin. Invest. 46, 829-837 (1967). 

Martinowitz U, Rabinovich J, Goldfarb D, Many A, Bank H. Interaction between warfarin sodium and amiodarone. N Engl J Med 1981 304(ll) 671-2. 

Tenidap sodium interacts with warfarin by displacing it from plasma albumin, although there may be another mechanism the dosage of warfarin may need to be reduced to avoid toxicity (7,10). 

The most widely prescribed anticoagulant in North American is warfarin sodium (Coumadin). It was discovered serendipitously in the early 1940s at the University of Wisconsin after hemorrhagic deaths occurred in cattle eating spoiled sweet clover. Warfarin is approved by the FDA for the prevention and treatment of VTE as well as for the prevention of thromboembolic complications associated with atrial fibrillation, heart valve replacement, and myocardial infarction. Because of its narrow therapeutic index, predisposition to drug and food interactions, and propensity to cause hemorrhage, warfarin requires... 

Ahmad S. Gemfibrozil interaction with warfarin sodium (Coumadin). Chest(l990 ) 98,1041-2. 

Claire RJ, Servis ME, Cram DL. Potential interaction between warfarin sodium and fluoxetine.(1991) 148, 1604. 

Warfarin is generally administered as the sodium salt and has 100% bioavailability. Over 99% of racemic warfarin is bound to plasma albumin, which may contribute to its small volume of distribution (the albumin space), its long half-life in plasma (36 hours), and the lack of urinary excretion of unchanged drug. Warfarin used clinically is a racemic mixture composed of equal amounts of two enantiomorphs. The levorotatory S-warfarin is four times more potent than the dextrorotatory R-warfarin. This observation is useful in understanding the stereoselective nature of several drug interactions involving warfarin. 

O Reilly RA. Interaction of sodium warfarin and disul-firam (antabuse) in man. Ann Intern Med 1973 78(l) 73-6. 

The oral dose of voriconazole does not have to be adjusted in patients who have renal impairment. However, intravenous administration of voriconazole should be avoided in these patients as the carrier vehicle sulfobu-tyl ether P-cyclodextrin sodium can accumulate in these patients. Dosage adjustment is required in patients who have chronic hepatic impairment. As voriconazole is a substrate for a number of cytochrome P450 enzymes, a number of clinically important dmg interactions occur with dmgs including ciclospotin, tacrolimus, phenytoin, warfarin, HIV protease inhibitors and non-nucleoside reverse transcriptase inhibitors. 

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