A medicinal composition which is in the form of granules, a powder or a preparation for syrup comprising memantine or a pharmaceutically acceptable salt thereof and an enteric polymer, said composition being easy to ingest even for aged people or patients having difficulty in swallowing and showing a reduced bitterness at administration. In particular, granules or a granular preparation for syrup wherein memantine or a pharmaceutically acceptable salt thereof and an enteric polymer are mixed together in granules.