PROBLEM TO BE SOLVED: To provide a patch for external use containing a basic drug, having high transdermal absorbability of the drug and excellent in stability.SOLUTION: The patch for external use includes at least one organic acid selected from the group consisting of oxybutynin acid addition salt, lactic acid and tartaric acid, and an organic acid salt and includes no water. The organic acid salt is preferably a metal salt of carboxylic acid, and more preferably sodium acetate.COPYRIGHT: (C)2011,JPO&INPIT【課題】薬物の経皮吸収性が高く、しかも安定性に優れた、塩基性薬物含有の外用貼付剤の提供。【解決手段】オキシブチニン酸付加塩、乳酸および酒石酸からなる群から選ばれる少なくとも1種の有機酸および有機酸塩を必須成分として水を含有しない外用貼付剤。有機酸塩は、カルボン酸の金属塩であるか、特に酢酸ナトリウムであることが好ましい。【選択図】なし
