"This study provides additional important data to better illustrate that marijuana is a dangerous drug that can be addictive," notes Dr. Alan I. Leshner, director of the National Institute on Drug Abuse (NIDA), National Institutes of Health, which funded the research. AIt also identifies the devastating impact marijuana dependence can have on young people and highlights the fact that many both need and want help dealing with their addiction. The challenge now becomes to develop highly effective methods to treat high risk adolescents dependent on marijuana."

The study's conclusions are based on interviews, medical examinations, social history, and psychological evaluations of 165 boys and 64 girls between the ages of 13 and 19 who had been referred by social service or criminal justice agencies to a university-based treatment program for delinquent, substance-involved adolescents. More than 80 percent of the males and 60 percent of the females in the survey met the adult clinical criteria for dependence on marijuana. More than two-thirds of the dependent teens complained of withdrawal symptoms when they stopped using marijuana, and over a quarter of them reported using more of the drug to relieve these symptoms.

Of the marijuana dependent teens, the study found that:

• 97 percent said they still used after realizing marijuana had become a problem for them;

• 85 percent noted that marijuana use interfered with driving and other situations at school, work, and home;

• 77 percent spent much time getting, using, or recovering from the effects of marijuana;

• 66 percent had given up important activities to use or acquire marijuana;

• 53 percent felt they had lost control and were using marijuana in larger amounts for longer periods than intended; and

• 35 percent wanted to cut back on use and had been unable to do so.

Most of the teens also reported that their behavioral problems predated, and were not initially caused by, their drug use.

Dr. Thomas Crowley, head of the research team conducting the study, cautions that these findings cannot be generalized to all adolescents. To be included in the study, youths had to have at least one diagnosis of drug dependence and three conduct disorder symptoms, including such things as frequent stealing, lying, running away, and, often, arrest. He points out, however, that, "About 825,000 youths were arrested and formally processed by juvenile courts in 1994. About 50 percent of these youths tested positive for marijuana at the time of arrest and many fit the profile of the teens in this study, making them at high risk for marijuana dependence."

This study is published in the spring issue of Drug and Alcohol Dependence, (Vol. 50, Issue 1).

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