PURPOSE OF REVIEW The recent heroin and prescription opioid misuse epidemic has led to a sharp increase in the number of opioid overdose deaths in the USA. Notwithstanding the availability of three FDA-approved medications (methadone, buprenorphine, and naltrexone) to treat opioid use disorder, these medications are underutilized. This paper provides an update from the recent peer-reviewed literature on barriers to the use of these medications. FINDINGS These barriers are interrelated and can be categorized as financial, regulatory, geographic, attitudinal, and logistic. While financial barriers are common to all three medications, other barriers are medication-specific. The adverse impact of the current opioid epidemic on public health can be reduced by increasing access to effective pharmacotherapy for opioid use disorder.