A method is provided for treating depression, and particularly major depression,by administering an effective amount of an SSRI medication that is augmented by administering an effective amount of an amphetamine prodrug, such as lisdexamfetamine, to patients receiving an SSRI medication. In particular, the amphetamine prodrug is administered to augment the effects of an SSRI medication in patients who respond poorly to the effects of the SSRI medication.