[Medicine 2.0: the stakes of participatory medicine].

Web 2.0: interactive, collaborative tools (wikis, social networks, blogs, virtual worlds) make Internet users active participants rather than simple consumers. Medicine 2.0: mentalities, approaches, and medical practices are changing, thanks to greater access to information, communal exchanges, and the comparison of personal experiences. Beyond the many wikis, blogs, and other collaborative tools, the site PatientsLikeMe.com stands out from the 2.0 crowd by its graphic representation of the clinical results entered by patients. Various European Web 2.0 sites exist as well. The risks reside in the reliability of information and the privacy of patient data. The challenges are to use these new resources to improve the quality of care and participate in the profound change they are bringing to the healthcare system.