Medication errors are common in the outpatient setting and frequently lead to emergency department visits and hospital admissions. The growth in social media use potentially provides a way to identify safety hazards quickly. This systematic review sought to examine whether social media could provide unique insights into safety issues compared to standard methods of detecting safety hazards. The included studies searched a variety of social media sites (e.g., Twitter, YouTube, and discussion forums) and found that a large number of adverse events are discussed in real time. Most of these events tended to be mild, such as symptoms or asymptomatic lab test abnormalities. Serious adverse events, those requiring urgent treatment or hospitalization, were relatively underrepresented. Although searching social media may help identify unique safety hazards, the investigators concluded that current evidence is insufficient to determine whether routine analysis of social media is of added benefit to traditional surveillance methods.