PROBLEM TO BE SOLVED: To provide an atopic dermatitis therapeutic that has high safety and is particularly effective against an itch.SOLUTION: An atopic dermatitis therapeutic has N-acyl tryptamine represented by the following formula (I) (where R is a C2-29 saturated aliphatic hydrocarbon group) or a pharmaceutically acceptable salt thereof, a hydrate or a solvate. It is particularly effective against an itch.SELECTED DRAWING: NoneCOPYRIGHT: (C)2020,JPO&INPIT【課題】安全性が高く、特に痒みに対して効果を示すアトピー性皮膚炎治療剤を提供する。【解決手段】次式（Ｉ）：【化１】（式中、Ｒは炭素数２～２９の飽和脂肪族炭化水素基を表す。）で示されるＮ－アシルトリプタミン、又はその薬学的に許容される塩、水和物もしくは溶媒和物を含有する、特に痒みに対して効果を示すアトピー性皮膚炎治療剤。【選択図】なし
