The optimal treatment of superficial venous thrombosis (SVT) is still uncertain. Though low molecular weight heparin (LMWH) is considered the treatment of choice, studies conducted so far do not give clear indications of the optimal dose and duration of treatment. This study aims to evaluate whether an intermediate therapeutic dose of LMWH (parnaparin) is more effective than a prophylactic dose and also to assess whether 10 rather than 30 days are sufficient for treatment.