Three medication treatments are recommended by the World Health Organization and are US Food and Drug Administration (FDA)-approved for treatment of opioid use disorder: 1) the opioid receptor full-agonist methadone, 2) the opioid receptor antagonist naltrexone (first approved in oral form for daily administration, and more recently as an extended-release monthly injection brand name: Vivitrol), and 3) the opioid receptor partial agonist buprenorphine, available as sublingual or buccal tablets or films, a skin patch (indicated for pain management), and extended-release parenteral formulations (injection or implant). The prognosis for opioid use disorder is poor if left untreated, with significant morbidity and mortality resulting from opioid overdose. It is estimated that 2.4 million Americans currently suffer from opioid use disorder, including individuals in virtually every region of the U.S. Opioid use disorder affects over 26 million individuals worldwide, with highest prevalence in the high-income countries of North America.
