Idiopathic intracranial hypertension (IIH) is a syndrome characterized by increased intracranial pressure (ICP), the absence of structural lesions on neuroimaging, and normal cerebrospinal fluid composition. Cerebral venous sinus thrombosis (CVST) is a common cause of increased ICP and can be differentiated from IIH with magnetic resonance venography. We describe a young woman with typical IIH who underwent lumbar puncture and was treated with a short course of high-dose corticosteroids followed by acetazolamide. She subsequently developed CVST, subarachnoid hemorrhage, and stroke. Risk factors that may have resulted in CVST are discussed.