[Drug therapy of deep venous thrombosis]

The cornerstone of therapy of deep venous thrombosis (DVT) of the lower extremities is anticoagulation. Surgical thrombectomy and thrombolytic treatment are restricted to a small number of selected patients. Anticoagulation is started either with unfractionated heparin (continuous intravenous infusion or subcutaneous injection b.i.d.) with dose adjustments according to the partial thromboplastin time (PTT), or with subcutaneous injections of low-molecular-weight heparin (LMWH) in one or two daily injections without laboratory monitoring. This initial treatment is rapidly followed and replaced by oral anticoagulants at an intensity corresponding to an International Normalized Ratio (I.N.R.) of 2-3 and for a duration of about 3 months after a first episode of proximal DVT. This duration should be modulated on an individual basis according to the risks of recurrent thromboembolism and hemorrhage.