• Medication assisted treatment (MAT) is effective for opioid use but rarely used during incarceration.
• This meta-analysis and systematic review examined the effectiveness of MAT in correctional settings.
• Methadone increases treatment entry and reduces opioid use and injection drug use post-release.
• Buprenorphine and naltrexone are as effective as methadone in increasing treatment entry.
• MATs did not decrease recidivism, but studies did not account for post-release engagement in MATs.
This study examined the state of the literature on the effectiveness of medication assisted treatment (MAT; methadone, buprenorphine, naltrexone) delivered in prisons and jails on community substance use treatment engagement, opioid use, recidivism, and health risk behaviors following release from incarceration. Randomized controlled trials (RCTs) and quasi-experimental studies published through December 2017 that examined induction to or maintenance on methadone (n = 18 studies), buprenorphine (n = 3 studies), or naltrexone (n = 3 studies) in correctional settings were identified from PsycINFO and PubMed databases. There were a sufficient number of methadone RCTs to meta-analyze; there were too few buprenorphine or naltrexone studies. All quasi-experimental studies were systematically reviewed. Data from RCTs involving 807 inmates (treatment n = 407, control n = 400) showed that methadone provided during incarceration increased community treatment engagement (n = 3 studies; OR = 8.69, 95% CI = 2.46; 30.75), reduced illicit opioid use (n = 4 studies; OR = 0.22, 95% CI = 0.15; 0.32) and injection drug use (n = 3 studies; OR = 0.26, 95% CI = 0.12; 0.56), but did not reduce recidivism (n = 4 studies; OR = 0.93, 95% CI = 0.51; 1.68). Data from observational studies of methadone showed consistent findings. Individual review of buprenorphine and naltrexone studies showed these medications were either superior to methadone or to placebo, or were as effective as methadone in reducing illicit opioid use post-release. Results provide the first meta-analytic summary of MATs delivered in correctional settings and support the use of MATs, especially with regard to community substance use treatment engagement and opioid use; additional work is needed to understand the reduction of recidivism and other health risk behaviors.