The number of U.S. residents using heroin for the first time fell by more than 50 percent in 2017, according to the latest National Survey on Drug Use and Health by the Substance Abuse and Mental Health Services Administration. Among other findings, the agency found that more people received treatment for substance use disorders in 2017 than in years past, especially those with heroin-related SUDs. Young adults (age 18-25) were more likely to use cigarettes, alcohol, cocaine, methamphetamine and LSD than their older counterparts, and more likely to have alcohol or heroin-related SUDs. They also have increasing rates of methamphetamine and marijuana use, serious mental illness and major depressive episodes, the agency said. Between 2015 and 2017, data also have trended in the wrong direction with respect to illicit drug use by pregnant women, the agency said. “The NSDUH data provide an essential roadmap for where we must focus our efforts,” said Elinore McCance-Katz, M.D., assistant secretary for mental health and substance use.