The number of new users of heroin decreased from 170,000 in 2016 to 81,000 in 2017, a one-year drop that would need to be sustained for years to reduce the number of fatal overdoses, experts said.
Fewer Americans are misusing or addicted to prescription opioid painkillers. And more people are getting treatment for heroin and opioid addiction, the survey found.
The Trump administration said the positive trends show government efforts are working.
Messages are reaching people about the dangers of heroin and the deadly contaminants it often contains on the street, Dr. Elinore McCance-Katz, an administration health official, said in a video presentation released with the figures.
Among the other findings:
—Marijuana use climbed in all age groups except young teenagers, with 2.5 percent of those 26 and older, or 5.3 million adults, reporting they use marijuana daily or almost daily last year.
—Methamphetamine and cocaine use climbed in young adults, ages 18 to 25. The uptick may indicate that users are shifting from opioids to other drugs, said Leo Beletsky, a public health policy expert at Northeastern University in Boston.
—Young adults have increasing rates of serious mental illness, major depression and suicidal thoughts.
—The number of new heroin users in 2017 — 81,000 — was lower than the numbers in most years from 2009 to 2016. But it was similar to the numbers of new heroin users in 2002 through 2008.
Experts said there's still work to be done before success can be declared.
"Taken together, this does not look like the portrait of a nation with improving mental health and addiction issues," said Brendan Saloner, an addiction researcher at Johns Hopkins Bloomberg School of Public Health. "It's hard to look at this and not think we need to be doing a better job than we're doing now."
Earlier this month, the Centers for Disease Control and Prevention released preliminary figures that appear to show a leveling off in overdose deaths in late 2017 and the first two months of this year.
Health officials have said it's too soon to say whether the nation's drug crisis has peaked. But in an interview with The Associated Press this week, U.S. Health and Human Services Secretary Alex Azar said several measures of the crisis are improving.
"We are making progress," he said. "We are seeing a flattening of our deaths from overdose."
AP Medical Writer Mike Stobbe in New York contributed to this report. Follow AP Medical Writer Carla K. Johnson on Twitter: @CarlaKJohnson
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