Blockchain-Powered Distributed Medical and Drug Record Sharing with Integrity and Access Control

Abstract

The rapid digital transformation of the healthcare and drug sector has increased the reliance on cloud infrastructures for storing and exchanging Electronic Health Records (EHRs), raising significant concerns regarding privacy breaches, unauthorized access, and data integrity. To overcome these challenges, this project proposes a secure, patient-centric medical and drug data-sharing framework that integrates blockchain technology with distributed cloud storage. In this system, patients upload encrypted Personal Health Records (PHRs) to an untrusted cloud server while maintaining complete control over access permissions. A semi-trusted Setup and Re-Encryption Server (SRS) manage cryptographic key generation and re-encryption processes, enabling healthcare providers to access only the data explicitly authorized by the patient. All access requests, key operations, and permission updates are immutably recorded on a blockchain ledger, ensuring transparency, traceability, and accountability. The design further enforces forward and backward access control, automatically revoking past privileges when permissions are modified. Experimental evaluation demonstrates that the framework effectively ensures confidentiality, integrity, and access control while resisting tampering and supporting efficient real-time medical services, making it a promising solution for secure and scalable e-Health data exchange.