Stable pharmaceutical composition

The invention relates to a stable pharmaceutical composition. The present invention provides a stable pharmaceutical composition containing (+)-11-[2-[2-[(diethylamino) methyl]-1-piperidinyl] acetyl]-5, 11-dihydro-6H-pyrido [2, 3-b] [1, 4] benzodiazepin-6-one or a salt thereof, and a pharmaceutical composition containing (+)-11-[2-[2-[(diethylamino) methyl]-1-piperidinyl] acetyl]-5, 11-dihydro-6H-pyrido [2, 3-b] [1, 4] benzodiazepin-6-one or a salt thereof. The present invention relates to a method for stabilizing 2, 3, 4] benzodiazepin-6-one or a salt thereof. 本申请涉及稳定的医药组合物。本发明提供含有(+)-11-[2-[2-[(二乙基氨基)甲基]-1-哌啶基]乙酰基]-5,11-二氢-6H-吡啶并[2,3-b][1,4]苯并二氮杂-6-酮或其盐的稳定的医药组合物、及(+)-11-[2-[2-[(二乙基氨基)甲基]-1-哌啶基]乙酰基]-5,11-二氢-6H-吡啶并[2,3-b][1,4]苯并二氮杂-6-酮或其盐的稳定化方法。