Variations of Prothrombin Time, Factor VII and Protein C with a Single Daily Dose of Acenocoumarol

Abstract
In 11 patients on steady anticoagulation with a daily dose of acenocoumarol, prothrombin time, factor VII and protein C were measured 2 and 16 h after the daily intake of acenoumarol. Prothrombin time (expressed as International Normalised Ratio) increases significantly, factor VII and protein C decrease between the two samples. These results suggest that a daily dose of acenoumarol is associated with fluctuation of the anticoagulant effect.