Methamphetamine overdoses are on the rise, a study published in JAMA Psychiatry says.

When researchers from the National Institute on Drug Abuse (NIDA) and the Centers for Disease Control and Prevention analyzed data from 2015 to 2019, they found that meth overdose deaths in the United States had almost tripled.

During that time span, meth-related overdoses rose from 5,526 to 15,489. This was accompanied by a 43 percent increase in people reporting meth use. Researchers believe more than 2 million adults used meth during the period, up from 1.4 million.

They used data from the National Vital Statistics System, which tracks births, deaths and the reasons people die. Then they looked at data from the National Survey on Drug Use and Health, which analyzes a random sample of adults in the United States.

The study shows stark differences in who uses meth. American Indians and Alaska Natives were the most likely to report methamphetamine-use disorder, meth injection and overall meth use. Black people who don’t inject meth also experienced a sharp rise in meth use, which increased more than tenfold.

Gay men had the highest prevalence of meth injection. More than three times the women who reported meth use in previous years said they used the drug between 2015 and 2019.

Age was a factor, too. Young adults 18 to 23 showed a fourfold increase in meth use without injection. Overall, the number rose by nearly half for all U.S. adults.

Riskier behavior also rose.

People reported more frequent meth use and more frequent use of methamphetamine and cocaine together. Those who inject meth were more likely to report that they used the drug more than 100 days per year. Riskier behavior might have been one reason that overdoses increased so sharply despite the number of users rising at a slower rate.

The people at greatest risk were those who experience other disparities linked to race, socioeconomic status and the criminal justice system.

Better prevention and treatment are needed, the researchers conclude.

“What makes these data even more devastating is that currently, there are no approved medications to treat methamphetamine use disorder,” Emily Einstein, NIDA science policy branch chief and co-author, said in a news release.