We studied the effects of intracarotid papaverine and prostaglandin E₁ incorporated in lipid microsphere (Lipo-PGE₁) in relation with transcranial Doppler parameters such as mean flow velocity (MFV) and pulsatile index (PI) of the proximal segment of the middle cerebral artery. Eighty patients with subarachnoid hemorrhage (SAH) were included in this study. In the case of angiographic vasospasm, papaverine at 7mg/min with total dose below 300mg per artery and 10-20 μg of Lipo-PGE₁ were injected in the supraclinoid portion of the internal carotid artery. Vasospasm was improved in 24 patients (63%), however, it was unchanged in 14 patients (37%). The former patients had more favora-ble outcomes than the latter patients (p<0.005). After intracarotid injection therapy, the correlation be-tween MFV and PI was classified into three types: type 1, both MFV and PI decreased; type 2, MFV decreased but PI increased; and type 3, both MFV and PI fluctuated. The Glasgow Outcome Scale 3 months after SAH was as follows: type 1 (n=15), good in 14 (93%) and moderate disability in one (7%); type 2 (n=9), good in eight (89%) and vegetative state in one (11%); and type 3 (n=14), moderate disability in five (36%), severe disability in seven (50%), and death in two (14%). Chi-square analysis showed significant differences between type 1 and type 3 (p<0.005), and type 2 and type 3 (p<0.005). In conclusion, intracarotid papaverine combined with Lipo-PGE₁ was effective for vasospasm but type 3 patients require a different treatment protocol.