PROBLEM TO BE SOLVED: To provide a technique for suppressing the color change of an aqueous composition comprising a halogenated isoquinoline derivative during storage at a high temperature.SOLUTION: An aqueous composition comprises a compound represented by general formula (1) in the figure, where X represents a halogen atom, or a salt thereof, or a solvate of them, and a prostaglandin.SELECTED DRAWING: None【課題】ハロゲン化イソキノリン誘導体含有水性組成物の、高温保存時の変色を抑制する技術の提供。【解決手段】次の一般式（１）［式中、Ｘはハロゲン原子を示す。］で表される化合物若しくはその塩又はそれらの溶媒和物、及びプロスタグランジン類を含有する、水性組成物。【選択図】なし
