New study: 1 in 5 Washington cannabis users show signs of addiction

New research finds that “cannabis use disorder” is common in Washington state, where weed has been legal for more than a decade.

“We're in a considerable natural experiment over the past 10 years of legalization. Washington state was one of the first states to legalize cannabis and we have a market of high potency cannabis products,” said Gwen Lapham, who co-authored the new study of patients in the Kaiser Permanente health care system.

Lapham and her colleagues found that just over 20% of users showed two or more symptoms of addiction, which might include failed efforts to quit using the drug, or frequent use that leads to issues at school, work, or home.

These findings highlight the need for health care providers to speak with patients about their cannabis use, Lapham said, so they can provide better care, especially in states like Washington where it’s now legal.

According to Lapham, such conversations might lead to addiction treatment, particularly in more severe cases. In some other cases, providers might recommend “potentially safer treatment alternatives” to cannabis for users who are using the drug to treat medical conditions.

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In a written statement, Paul Armentano, the deputy director of the cannabis advocacy group NORML, challenged some of the findings in the new study. He pointed to earlier research, for instance, which found a decline in cannabis use disorder after legalization.

He also said the risk of dependence from cannabis is far lower than from alcohol, opiates, or tobacco.

“Most people who experiment with pot do not experience extreme addiction or dependence,” Armentano wrote.