The effects of opioid policy changes on transitions from prescription opioids to heroin, fentanyl and injection drug use: a qualitative analysis

Background

Beginning in the 1990s, non-medical use of prescription opioids (POs) became a major public health crisis. In response to rising rates of opioid dependence and fatal poisonings, measures were instituted to decrease the prescription, diversion, and non-medical use of POs including...