Traditional forms of health information dissemination have previously involved a few key organizations originating health-related information and disseminating this to clinicians and the community. This information was typically disseminated via private, formalized and non-digital interactions between health information sources (HIS) and clinicians and consumers. With the introduction of the Internet, Web-based health information dissemination led to some changes with greater availability of online health information. However the recent adoption and uptake of social media has led to many more parties, both organizations of varying types, and individuals, participating in public health information dissemination; and this has also led to new forms of sharing health-related information, particularly involving a greater role for individuals. In this paper we introduce empirical findings in relation to how organizations and individuals are now using social media for sharing health information, and from this suggest themes to describe the changes from traditional to contemporary health information dissemination, as well as the new emerging roles and forms of interaction for health information dissemination.