ObjectiveTo systematically review the current published literature that uses social media data and internet search engine queries to identify emerging themes on the use of cannabis as a medicine. In this study, the term cannabis as a medicine refers to the use of cannabis with therapeutic intent and includes prescribed cannabis, over-the-counter cannabis, and non-prescribed cannabis used specifically for self-medication (not for recreational purposes).Materials and MethodsFor this systematic review, Medline, Scopus, Web of Science and Embase databases were searched for peer reviewed studies published in English between January 2010 and March 2022. All study types that examined social media data and cannabis as a medicine were included in the review.ResultsForty studies were included in this review. 21 studies used manually labeled data, 4 studies used existing meta-data, 2 studies used data from social media analytics companies and 13 used computational methods for annotating data. More than half of the studies 22/40 (55%), were published in the last three years. The incidental use of cannabis as a medicine was found in eleven studies that were focused on more general health-related issues, rather than on medicinal cannabis only.ConclusionOur systematic review has revealed the growing interest in analyzing user-generated content for studying cannabis as a medicine. This review has also highlighted the need for studies into cannabis use for specific health conditions and for automatic processing of larger datasets using computational methods (machine learning technologies).