Background Physicians, patients and others involved need to have accurate information on patients' current drug prescriptions available, and have that information protected from unauthorized access. During the past decade, many counties in Sweden have implemented regionally shared medication lists within health care. Objective The aim of this study was to describe physicians' views on changes in accuracy, availability and confidentiality in the transition from local medication lists to a regionally shared medication list. Setting Health care units in four different counties of Sweden after the transition from local medication lists to a regionally shared medication list. The shared medication list was an integrated part of the electronic health record system in the respective counties, but the system and implementation process varied. Methods Physicians (n = 7) with experience of transition from local medication lists to a regionally shared medication list were interviewed in a semi-structured manner. Main outcome measure: Physicians' views on changes in information risks, focusing on accuracy, availability and confidentiality. Results The transition from local medication lists to a shared medication list increased the availability of information: from being time consuming or not possible to access from other care givers to most information being available in one place. A regionally shared medication list was perceived as having the potential to provide a greater accuracy of information, but not always: the shared medication list was perceived as more complete but with more non-current drugs. On the other hand, a shared medication list implied an increased risk of violating patient privacy, placing greater demands on IT security in order to protect the confidentiality of information. Conclusion Physicians perceived a regionally shared medication list to increase the availability of information about current prescriptions and potentially the accuracy but may decrease the confidentiality of information. To implement a shared medication list, we recommend providing clear description of responsibilities and routines for normal activities as well as back-up routines, consider IT-security and data protection early, involve patients to improve the accuracy of the list as well as to monitor and evaluate the implementation.