Opioid crisis in the USA and Canada: how and why did this happen?

In the last few decades, there has been an epidemic increase in opioid use disorder and fatal opioid overdose in the United States and Canada, which allows us to state the presence of an opioid crisis. The opioid epidemic is believed to have begun due to a significantly low threshold for prescribing narcotic analgesics to treat chronic pain. This subsequent tightening of medical opioid dispensation led to the resurgence of the unlawful drug market, which included heroin and fentanyl. The review article provides data from a special commission established with the supporting of Stanford University and The Lancet Journal to understand and overcome the opioid crisis in North America, as well as analyzes other literary sources.