The invention relates, in one aspect, to a mucoadhesive edible slow dissolving film comprising a salt of alginic acid, an edible cellulose derivative, an edible protein, and edible polymer delaying the dissolution in a physiological fluid of the edible film selected from polyvinylpyrrolidone, a carboxyvinyl polymer and mixtures thereof, in an amount effective to delay the dissolution time of the film in a biological fluid. The edible film is suitable for cicatrizing oral ulcerations or lesions or for forming a layer on oral mucosae or gingiva affected by ulcerations or lesions for protecting against mechanical abrasions, infections or caustic agents.
