An object of the present invention is to provide a novel pharmaceutical composition containing donepezil, which is already used as a remedy for the treatment of dementia (cognitive impairment), in order to increase options for administration methods and improve patient compliance. The present invention provides a pharmaceutical composition containing donepezil or a pharmaceutically acceptable salt thereof and a naturally-occurring polymer, the pharmaceutical composition further containing at least one of edetate, sulfite, dibutylhydroxytoluene and butylhydroxyanisole.
