High doses of warfarin are more beneficial than its low doses in patients with deep vein thrombosis

Abstract

Background: The efficacy and safety of enoxaparin in outpatient treatment of deep vein thrombosis have been well studied. The present study aimed to compare the efficacy of a 10-mg loading dose of warfarin with 5 mg of the drug and enoxaparin in achieving the international normalized ratio (INR) range. Methods: This randomized clinical trial was performed in the emergency department (ED) of our study. International normalized ratio was checked daily for 7 days and on the 14th day. Based on the patient's INR on the third day, the doses were adjusted. Patients received enoxaparin (1.5 mg/kg per day) simultaneously until the therapeutic range of INR was achieved for 2 consecutive days. Result: The side effects were compatible in both groups. There was a significant difference in the INR rates of the 2 groups recorded on the third, fourth, and seventh days. Conclusion: The 10-mg loading dose of warfarin induces the therapeutic range of INR earlier than the 5-mg dose without causing any significant difference in the side effects. More cases in the 10-mg group had INR levels higher than 3; the very dose, therefore, is recommended as the loading dose in cases of outpatients with deep vein thrombosis referring to the ED. Tight control of INR, after the third day of treatment, is also recommended in these cases. (C) 2011 Elsevier Inc. All rights reserved.