Ulcerative colitis is associated with a number of extraintestinal complications, including the infrequent occurrence of thromboembolic disease. Cerebral venous thrombosis is extremely rare, with only 15 cases reported in the literature. The outcome in this group of patients is poor; the result in more than 80% of the cases is permanent neurologic sequelae or death. The precise mechanisms involved in thrombogenesis remain unclear. A hypercoagu-lable state may occur in ulcerative colitis because of well-documented associations of thrombocy-tosis, elevated factors V and VIII and fibrinogen, and decreased antithrombin III. Treatment regimens for cerebral venous thrombosis remain controversial and include anticoagulation with heparin, surgical thrombectomy, and systemic and local infusion of fibrinolytic regimens. A conservative approach with antiedemic agents, anticonvulsants, antiplatelet therapy, and acet-azolamide also may be beneficial and offers a substantially reduced hemorrhagic potential. A case of primary superior sagittal sinus thrombosis associated with active ulcerative colitis treated by the latter method is reported. The patient's neurologic recovery was complete, with recanalization of the thrombosed venous sinus being demonstrated by magnetic resonance imaging studies.