From on September 3, 2014:

Marijuana never stops making headlines, especially after some American states legalizing it. Opinion about the pros and cons of smoking are widely divided.

A research by the Massachusetts General Hospital found that youngsters treated for outpatient substance use disorder had signs of cannabis withdrawal.

“Our results are timely given the changing attitudes and perceptions of risk related to cannabis use in the U.S.,” senior author, John Kelly, PhD, of the Center for Addiction Medicine in the MGH Department of Psychiatry, said in a press release. “As more people are able to obtain and consume cannabis legally for medical and, in some states, recreational use, people are less likely to perceive it as addictive or harmful. But research shows that cannabis use can have significant consequence

For the study, the researchers examined 127 participants aged between 14 and 19. The teens were being treated as outpatients for substance use disorder. Researchers noted that 90 of the participants reported smoking pot often. The researchers monitored the drug use of the teens, withdrawal symptoms, psychiatric symptoms and consequences at the beginning of the study as well as at three, six and 12 months by conducting interviews/surveys. The researchers then divided the participants into two groups based on people with or without cannabis withdrawal symptoms.

Researchers found that of the 90 cannabis users, 76 of them, or 84 percent, showed signs of cannabis dependence. The symptoms were increased tolerance, increased use, inability to reduce or stop using and continued use regardless of medical or psychological issues caused by cannabis. Overall, 36 respondents or 40 percent reported suffering from withdrawal symptoms.

The authors said that at the beginning of the study, substance use and consequences from it were more in the teens that confessed experiencing withdrawal symptoms. These teens also reported a higher incidence of mood disorders. Consequences from substance abuse included missing schoolwork, poor job performance, financial issues and relationship complications.

The researchers also found that people who thought they had a problem showed a small improvement in substance use. People who did not think that they had a problem but suffered from withdrawal symptoms had an initial increase in abstinence. However, cannabis use increased after three months.

“We hypothesize that participants who experience withdrawal symptoms but do not recognize having a substance use problem may not attribute those symptoms to cannabis withdrawal,” explained Claire Greene, MPH, corresponding author of the report. “Those who do acknowledge a substance-use problem may correctly attribute those symptoms to cannabis withdrawal, giving them even more motivation to change their substance use behavior.”

The study, ‘The Prevalence of Cannabis Withdrawal and Its Influence on Adolescents’ Treatment Response and Outcomes: A 12-Month Prospective Investigation,’ was published in the Journal of Addiction Medicine.