Continuous technological progress has been supporting health providers with powerful tools to help them improve the delivery of health services and ensure patients’ safety. These adopted technologies focus on data collection. However, patients’ data are distributed and fragmented, which highly affects the quality of care. In this paper, we propose a blockchain-based approach to improve the management of patients’ data by addressing: the adverse drug interactions or reactions due to inappropriate medication intake. Although the initial target of our contribution is the healthcare system in Lebanon, our solution can be applied to improve any healthcare system. It combines the usage of a blockchain with Semantic Web technologies, where the blockchain provides a secure infrastructure for data sharing and prevents data tampering through a tamper-proof audit log. As for the semantic description of data, it brings a common shared understanding of the data at hand, boosting knowledge discovery, and automating decision making.