Fondaparinux pharmacokinetics

Subcutaneous fondaparinux 4 mg was given daily for 5 days to 12 healthy subjects, with warfarin 15 mg given on day 4 and 10 mg on day 5 in a placebo controlled study. Warfarin had no effect on fondaparinux pharmacokinetics. In addition, the effect of warfarin on prothrombin time was not altered by fondaparinux. The authors concluded that the prothrombin time (INR) can still be used to monitor the effect of oral anticoagulants during the switch from fondaparinux to oral anticoagulants. ... 

A single 975-mg dose of aspirin given on day 4 of an 8-day course of subcutaneous fondaparinux 10 mg daily had no effect on fondaparinux pharmacokinetics in 16 healthy subjects. The increase in bleeding time with fondaparinux and aspirin was greater than with aspirin alone, but this was not statistically significant. Aspirin had no effect on the small prolongation of aPTT seen with fondaparinux. ... 

Donat p Duret JP Santoni A, et al. The pharmacokinetics of fondaparinux sodium in healthy volunteers, Clin Pharmacokinet 2002 41 Suppl 2 1-9,... 

Fondaparinux sodium, a selective inhibitor of coagulation factor Xa, is eUminated by the kidneys. In a randomized, crossover study in 24 healthy volunteers the pharmacokinetics and pharmacodynamics of digoxin 0.25 mg/day orally for 7 days were unaffected by fondaparinux sodium 10 mg/day subcutaneously for 7 days (260). 

In a randomized, crossover study in 24 healthy volunteers, the pharmacokinetics of fondaparinux sodium 10 mg/day subcutaneously for 7 days were unaffected by digoxin... 

In healthy volunteers, steady-state fondaparinux did not alter the pharmacodynamic effects of a single dose of piroxicam 20 mg (23). Piroxicam did not alter the pharmacokinetics of fondaparinux. 

Ollier C, Faaij RA, Santoni A, Duvauchelle T, van Haard PM, Schoemaker RC, Cohen AF, de Greef R, Burggraaf J. Absence of interaction of fondaparinux sodium with aspirin and piroxicam in healthy male volunteers. Clin Pharmacokinet 2002 41(Suppl 2) 31-7. 

The pharmacological studies described show that the pharmacokinetics of fondaparinux are not changed by aspirin and piroxicam, and that there is only a minor increase in bleeding time. Nevertheless, the manufacturers of... 

Lieu, C. Shi, J. Donat, F. Van Horn, R. Brian, W. Newton, J. Delbressine, L. Vos, R. Fondaparinux sodium is not metabolised in mammalian Uver fractions and does not inhibit cytochrome P450-mediated metabolism of concomitant drugs, Clin.Pharmacokinet., 2002, 4i(Suppl. 2), 19-26. 

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