One of the most interesting glycosaminoglycans (GAGs) is heparansulphate, known as the physiological activator of antithrombin III and involved in the maintenance of the antithrombotic potential of uninjured endothelium. The aim of our study was to evaluate the tolerability and effectiveness of heparansulphate with respect to sulodexide, another GAG suitable for the treatment of venous diseases. The study was performed in a open-label, controlled, with parallel and randomized groups, design. Thirty patients (aged 32-72 years) suffering from superficial thrombophlebitis were treated for two weeks with heparansulphate 100 mg t.i.d. or sulodexide 250 LSU b.i.d., both given orally. Some coagulative and fibrinolytic parameters (PT; aPTT; fibrinogen; euglobulin lysis time; t-PA; PAI-1; ATIII; alpha 2-antiplasmin; D-Dimer and platelets count) were assayed at the beginning and at the end of the study. Moreover signs and symptoms of disease (skin trophism; local pain; itch and oedema) were assessed. Heparansulphate and sulodexide were able to reduce signs and symptoms with similar degree and to significantly modify t-PA, alpha 2-antiplasmin and ATIII levels without any difference between treatments. Our issues show that heparansulphate can be useful in superficial thrombophlebitis management.