OBJECTIVE We examined the therapeutic benefits of intra-arterially administered papaverine for treatment of symptomatic cerebral vasospasm after subarachnoid hemorrhage (SAH). Recent advances in microcatheter technology have facilitated endovascular approaches to vessels experiencing vasospasm after SAH. However, despite numerous encouraging anecdotal reports, no rigorous examination of the efficacy of these procedures has been published. Intra-arterial infusion of papaverine has become part of the standard management of vasospasm at some centers. METHODS We examined a series of 31 patients undergoing papaverine infusion for the treatment of symptomatic vasospasm after SAH. The patients were a subgroup of the series enrolled in the North American Trial of Tirilizad for Aneurysmal Subarachnoid Hemorrhage. These individuals were matched with patients from the same trial who exhibited similar clinical characteristics (including the degree of vasospasm and the modified Glasgow Coma Scale scores measured at the time of admission and on the day of papaverine infusion) but received medical management alone for vasospasm. RESULTS Logistic regression analysis comparing these two groups showed no statistical difference in the 3-month Glasgow Outcome Scale scores between patients receiving papaverine and control subjects (58% favorable outcomes for control subjects versus 45% for patients receiving papaverine). CONCLUSIONS Although isolated series documenting clinical successes have prompted the increased use of papaverine as a treatment for vasospasm after SAH, this series suggests that, as it is currently being used, the drug does not provide added benefits, compared with medical treatment of vasospasm alone. This result does not preclude the possibility that alterations in the timing of or indications for drug treatment might produce beneficial effects.