A stable pharmaceutical composition is provided. The pharmaceutical composition comprises: (a) a medium system, comprising a first component, a second component and a third component, wherein the first component is a phosphate buffered saline, the second component is selected from the group consisting of vegetable oils, animal oils, fatty acids and combinations thereof, and the third component is selected from the group consisting of polyethylene glycol, dimethyl sulfoxide (DMSO), ethanol, propylene glycol, polysorbate, polyoxyethylated vegetable oil, ethyl acetate, 2- hydroxyethyl 12-hydroxyoctadecanoate, tocopheryl polyethylene glycol succinate and combinations thereof and (b) n- butylidenephthalide (BP).
