Fact Opioid painkillers like Vicodin® and OxyContin® are chemically similar to heroin. 20 9 6 3 What do you think? 38 Reactions Share it out Source 1: NIDA. Opioids. National Institute on Drug Abuse website. https://www.drugabuse.gov/drugs-abuse/opioids. . Accessed May 11, 2018. https://www.drugabuse.gov/drugs-abuse/opioids Issue Opioids Topics Heroin, Painkillers More Facts