Pseudotumor cerebri is frequently the only clinical clue to the presence of cerebral venous thrombosis, a potentially devastating condition. We report a case of pseudotumor cerebri associated with thrombosed dural venous sinuses caused by propagation of a catheter-related subclavian vein thrombus. The findings and clinical course in this case alert us to a complication of central venous catheter use that responds well to treatment if recognized early.