Almost six million American adults experienced marijuana use disorder in the past year, according to a study by scientists at the National Institutes of Health (NIH).
Symptoms of marijuana use disorder include cravings, developing a tolerance, and experiencing withdrawal symptoms, including inability to sleep, nervousness, anger, or depression, within a week of stopping heavy use, according to Medical Daily.
The study, published in the American Journal of Psychiatry, found 6.3 percent of adults acquire a dependence on marijuana at some point in their lives, and 2.5 percent of adults have experienced marijuana use disorder in the past year. The researchers interviewed more than 36,000 adults about their drug and alcohol use, and related psychiatric conditions.
They found marijuana use disorder is about twice as common in men than women. Younger people are much more likely than those over 45 to experience the disorder.
The researchers note cannabis dependence is strongly and consistently associated with mental health disorders, as well as other substance use disorders.
The study found people with marijuana use disorder, particularly those with severe forms of the disorder, experience considerable mental disability.
The researchers found only about 7 percent of people with past-year marijuana use disorder receive any marijuana-specific treatment, compared with slightly less than 14 percent of people with lifetime marijuana use disorder.
“These findings demonstrate that people with marijuana use disorder are vulnerable to other mental health disorders,” Nora D. Volkow, M.D., Director of the National Institute on Drug Abuse, said in a news release. “The study emphasizes the need for such individuals to receive help through evidence-based treatments that address these co-occurring conditions.”
NIH scientists say because many people use marijuana and alcohol together, more research is needed on the effects of their combined use.