1. Opioid use decreased in Medicare Part D, while medication-assisted treatment increased Publication: [Washington, D.C.] : U.S. Department of Health and Human Services, Office of Inspector General, July 2019 Subject(s): Analgesics, Opioid -- therapeutic useMedicare Part DOpiate Substitution TreatmentOpioid-Related Disorders -- drug therapyDrug Overdose -- drug therapyDrug Utilization -- trendsForecastingInappropriate PrescribingNaloxone -- therapeutic useState GovernmentHumansUnited States