Systems and methods for a patient authorized medical information storage and access system. One of the methods includes receiving information indicating a transaction is to be performed between two entities, the transaction indicating an event associated with transfer or receipt of medical information; accessing a patient master index to confirm that the two entities are authorized to transfer or receive the medical information; causing generation of a blockchain transaction between the two entities; updating the patient master index to reflect the transaction; and enabling access, by a receiving entity of the two entities, to the medical information.