We expect computerized systems in medical settings, such as prescription check systems, to prevent medical accidents caused by drugs. To create such systems, we need drug information databases. However, existing databases lack suitable data schema and inherit the problem of original data, ethical drug package inserts. Though their standpoint involves utilizing package insert information to build databases, we adopt another standpoint in this study by initially implementing a drug information database, and then generating package inserts based on the information therein. In this paper, we particularly focus on a composition database and propose its schema.