Pharmacy structural formula (i) of the effective quantity:< Conversion 1 >So the salt or the false crystal multi types where pyrazolone chemical compound or that chemical compound which is displayed is allowed pharmacy is included, the remedy of the brain blood vessel obstacle where density in the blood plasma of the not yet change body is maintained specified period uniformly, as shown the effect whose at the same time chemical compound is higher, is prescribed at the dosage quantity which is controlled, is related to the brain circulating incompletion of the brain blockage and the like.薬学的に有効量の構造式(I):【化1】で表されるピラゾロン化合物、又はその化合物の薬学的に許容される塩、又は擬似結晶多型を含み、未変化体の血漿中濃度が所定の期間一定に維持され、かつ化合物がより高い効果を示すように制御された投与量で投与される、脳梗塞などの脳循環不全に関連する脳血管障害の治療薬。
