PROBLEM TO BE SOLVED: To provide a prophylactic/therapeutic agent for depression, having few adverse side effects and being effective for a depression patient whose conditions are hardly ameliorated by conventional antidepressant agents and for preventing the recurrence of depression in a patient who receives the administration of an antidepressant agent at a reduced dose or for whom the administration of an antidepressant agent is discontinued.SOLUTION: The prophylactic/therapeutic agent for depression contains ferulic acid or a pharmaceutically acceptable salt thereof as an active ingredient and is preferably an oral preparation.COPYRIGHT: (C)2012,JPO&INPIT【課題】副作用が少なく、また従来の抗うつ薬によっても改善しにくいうつ病患者や、抗うつ薬の投与を減量ないし中止した患者の再発予防に対しても有効な、うつ病予防・治療剤の提供。【解決手段】フェルラ酸又はその薬学的に許容される塩を有効成分とするうつ病予防・治療剤。【選択図】なし