BACKGROUND The direct oral thrombin inhibitor dabigatran has a predictable anticoagulant effect and may be an alternative therapy to warfarin for patients who have acute venous thromboembolism. METHODS In a randomized, double-blind, noninferiority trial involving patients with acute venous thromboembolism who were initially given parenteral anticoagulation therapy for a median of 9 days (inte...

Warfarin, a commonly prescribed anticoagulant, exhibited large inter-individual and inter-ethnic differences in the dose required for its anticoagulation effect. Asian populations, including Chinese, require a much lower maintenance dose than Caucasians, for which the mechanisms still remain unknown. We determined DNA sequence variants in CYP2C9 and VKORC1 in 16 Chinese patients having warfarin...

Vitamin K antagonists (VKAs) have been used to treat thromboembolic disease for over 60 years, and they continue to be the most commonly prescribed anticoagulants worldwide. However, VKAs such as warfarin have a narrow therapeutic index, and the mean daily dose of warfarin varies widely from patient to patient. Underdosing can leave patients undertreated for their thromboembolic diseases; overd...

Vitamin K antagonists (VKAs) such as warfarin are the only oral anticoagulants currently available for clinical use. Warfarin has numerous limitations, including slow onset and offset of action, a narrow therapeutic window, and a metabolism that is affected by diet, drugs, and genetic polymorphisms.1 Because of its unpredictable dose response, warfarin requires careful coagulation monitoring to...

A significant proportion of warfarin dose variability is explained by variation in the genotypes of the cytochrome P450 CYP2C9 and the vitamin K epoxide reductase complex, VKORC1, enzymes that influence warfarin metabolism and sensitivity, respectively. We sought to develop an optimal pharmacogenetic warfarin dosing algorithm that incorporated clinical and genetic information. We enroled patien...

BACKGROUND Drug interaction studies selecting patients in a real-life setting are scarce, and most studies to date are characterized by a small sample size. OBJECTIVE To evaluate the effect of amiodarone on warfarin maintenance dose and adverse events in an anticoagulation cohort from a tertiary cardiovascular service. METHODS This study recruited 866 patients, and oral anticoagulant therap...

Many guidelines for the management of antithrombotic therapy in endoscopic procedures state that warfarin should be replaced by heparin in high risk endoscopic procedures. However, heparin bridging therapy is costly, requires a long hospital stay, and is indicated as a risk factor for bleeding after endoscopic submucosal dissection (ESD). It is not yet clear whether it is better to perform gast...

Warfarin anticoagulation effect is characterized by marked variability, some of which has been attributed to CYP2C9 polymorphisms. This study prospectively examines whether a priori knowledge of CYP2C9 genotype may improve warfarin therapy. Patients were randomly assigned to receive warfarin by a validated algorithm ("control", 96 patients) or CYP2C9 genotype-adjusted algorithms ("study", 95 pa...