[Self-monitoring and self dosing of oral anticoagulant therapy with vitamin K antagonists]

Anticoagulant therapy with vitamin K antagonists is effective in the prevention and treatment of thrombotic disease. The variable effect of these agents and the relatively small therapeutic width necessitate frequent checks on the intensity of the anticoagulation therapy as well as frequent dose-adjustments. Recently, small and reliable portable machines have become available which enable patients themselves, by means of a drop of blood obtained from a finger prick, to measure the intensity of the anticoagulation therapy and if necessary to adjust the treatment dose. In studies within the Netherlands where (selected) patients determined the 'international normalised ratio' (INR) themselves and if necessary adjusted the dose of the anticoagulant medication, the INR was mostly within the therapeutic target area. Furthermore, the independence, the possibility for travelling and the time saved were experienced as positive aspects. Under certain conditions, allowing patients themselves to check the INR and if needs be to adjust the dose of the anticoagulation treatment, may be an acceptable alternative for anticoagulation therapy check-ups performed by the thrombosis service.