Thrombolytic agents previously employed in the treatment of ischemic stroke were associated with adverse side-effects and hemorrhagic complications. The use of streptodekase (S), a Soviet trombolytic drug, which is a long-acting immobilized ensyme proved to be highly effective. The efficacy of S in ischemic stroke was not investigated. The authors report the use of S within the first 6-8 hours after an ischemic stroke in thrombosis of the main stem of the middle meningeal artery in one case and of the vertebral and main arteries with the development of the locked-in syndrome in the other. In both cases the administration of S led to thrombolysis and restoration of the blood flow. The authors discuss the results of the use of S and indicate the necessity of the earliest possible administration of the drug with regard to a high sensitivity of the brain to ischemic lesions.