PROBLEM TO BE SOLVED: To provide a therapeutic or prophylactic agent for behavioral psychological symptoms or dementia accompanied by behavioral psychological symptoms, which does not cause any accessory symptom (adverse side effect) such as accidental aspiration, falling, oversedation, cognitive deterioration and cardiac infarction and does not induce pseudoaldosteronism even when administered for a long period.SOLUTION: A therapeutic or prophylactic agent for dementia comprises fluvoxamine or a pharmaceutically acceptable fluvoxamine salt as an active ingredient. A therapeutic or prophylactic agent for dementia accompanied by behavioral psychological symptoms comprises fluvoxamine or a pharmaceutically acceptable fluvoxamine salt as an active ingredient.COPYRIGHT: (C)2014,JPO&INPIT【課題】本発明は、誤嚥、転倒、過鎮静、認知力低下、心筋梗塞などの随伴症状(副作用)を起こすことが無く、長期投与によっても偽アルドステロン症が出現することの無い行動心理学的症候ないしそれを伴う認知症の治療又は予防剤を提供することを目的とする。【解決手段】フルボキサミン又は製薬上許されるフルボキサミン塩を有効成分とする認知症の治療又は予防剤。フルボキサミン又は製薬上許されるフルボキサミン塩を有効成分と行動心理学的症候を伴う認知症の治療又は予防剤。【選択図】なし