PROBLEM TO BE SOLVED: To provide a film-like external preparation for periodontitis with a long intraoral residence time and to provide a method of use thereof.SOLUTION: The above subject is solved by a film-like external preparation for periodontitis for the treatment or prevention of periodontitis by attaching to a users teeth and/or gingiva at the time of sleep and by a method thereof. The film-like external preparation for periodontitis contains at least an edible water soluble film formation compound and an active ingredient of a drug for treating or preventing periodontitis, has a laminated structure constituted from two or more layers comprising the lowest adhesive layer and the highest protective layer on the side directly attached to the teeth and/or gingiva, and is capable of completely dissolving in the saliva, wherein the lowest adhesive layer contains the above active ingredient of a drug, and has higher adhesiveness to the teeth and/or gingiva than the highest protective layer, and the highest protective layer has a lower dissolution rate against the saliva than the lowest adhesive layer.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2016,JPO&INPIT【課題】口腔内での滞留時間が長い、歯周病用フィルム状外用剤及びその使用方法を提供すること。【解決手段】睡眠時に使用者の歯及び/又は歯肉に貼り付けて歯周病を治療又は予防する歯周病用フィルム状外用剤であって、該歯周病用フィルム状外用剤は、可食性の水溶性フィルム形成化合物及び歯周病を治療又は予防する薬効成分を少なくとも含有し、歯及び/又は歯肉に直接貼り付ける側の最下接着層及び最上保護層を含む2層以上で構成される積層構造を有し、該最下接着層は上記薬効成分を含有し、該最下接着層の方が該最上保護層より歯及び/又は歯肉に対する接着性が高く、該最上保護層の方が該最下接着層より唾液に対する溶解速度が遅いものであり、該歯周病用フィルム状外用剤は唾液に完溶し得るものである歯周病用フィルム状外用剤及びその方法により課題を解決した。【選択図】図1
