A new study suggests marijuana smokers may be significantly more likely to develop an addiction to other drugs and alcohol than people who don’t use marijuana.
The study, published in JAMA Psychiatry, included almost 35,000 adults who were interviewed three years apart. At the time of the first interview, almost 1,300 used marijuana. After three years, two-thirds of people who used marijuana had some form of substance use disorder, compared with less than 20 percent of people who did not use marijuana in the previous year.