ISSN:
1432-1041
Keywords:
warfarin
;
cimetidine
;
ranitidine
;
stereochemistry
;
drug-drug interaction
;
pharmacokinetics
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Medicine
Notes:
Summary Stereochemical aspects of the potential interaction between the oral anticoagulant warfarin and the H2-antagonists, cimetidine and ranitidine, were investigated. A single 25 mg oral dose of racemic warfarin was administered on Day 4 of a randomised 9-day multiple dosing regimen of either cimetidine (800 mg o.d.) ranitidine (300 mg o.d.) or placebo. The degree of anticoagulation produced by warfarin was quantificated by the determination of both the prothrombin and Factor VII clotting times. Ranitidine had no effect on the pharmacodynamics of warfarin or the pharmacokinetics of the individual warfarin enantiomers. Cimetidine whilst producing no statistically significant change in the pharmacodynamics of warfarin or in the pharmacokinetics of the pharmacologically more potent (S) enantiomer, did produce a statistically significant decrease in the clearance of the (R) enantiomer, possibly due to metabolic inhibition of this species.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00542190