PROBLEM TO BE SOLVED: To provide a P2X4 receptor antagonist.SOLUTION: A preventive or therapeutic agent of neurogenic pain contains a diazepinedione derivative expressed by 5-(3-hydroxyphenyl)-1H-naphtho[1,2-b][1,4]diazepine-2,4(3H,5H)-dione, etc. or a pharmacologically acceptable salt thereof as an active ingredient.COPYRIGHT: (C)2012,JPO&INPIT【課題】P2X4受容体拮抗剤の提供。【解決手段】5-(3-ヒドロキシフェニル)-1H-ナフト[1,2-b][1,4]ジアゼピン-2,4(3H,5H)-ジオン等で表されるジアゼピンジオン誘導体又はその薬理学的に許容される塩を有効成分として含有する神経因性疼痛の予防又は治療剤。【選択図】なし