Leave it to NIDA to remind us of the "Adverse Health Effects of Marijuana Use." In a new article published in the New England Journal of Medicine, four doctors report that "the question of whether marijuana is harmful remains the subject of heated debate."
Written by NIDA's director Dr. Nora Volkow and three others, they focus on the alleged negative effects of marijuana, such as addiction, the gateway to other drugs, increased potency and the risk of cancer. On the positive side, getting lung cancer from marijuana use is considered low and the risk "unclear." And the authors acknowledge "policy shifts toward legalization of marijuana."
But the overall tone of the review is predictably dire. "Heavy marijuana use has been linked to lower income, greater need for socioeconomic assistance, unemployment, criminal behavior and lower satisfaction with life, " they contend. In a chart, addiction to marijuana and other substances, diminished lifetime achievement, motor vehicle accidents and symptoms of bronchitis are all listed as high, while abnormal brain development, progression to use other drugs, schizophrenia, and depression and anxiety are ranked as medium.
"There is also a need to improve our understanding of how to harness the potential medical benefits of the marijuana plant without exposing people who are sick to its intrinsic risks," they state. "Some physicians continue to prescribe marijuana for medicinal purposes despite limited evidence of a benefit. This practice raises particular concerns with regard to long-term use by vulnerable populations."
The conditions listed that "may be relieved by treatment with marijuana or other cannabinoids" are glaucoma, nausea, AIDS-associated anorexia and wasting syndrome, chronic pain, inflammation, multiple sclerosis and epilepsy.
The review calls for new research so we can truly understanding the effects - both negative and positive - of marijuana use on individuals and society. "Studies in states (e.g., Colorado, California, and Washington) and countries (e.g., Uruguay, Portugal and the Netherlands) where social and legal policies are shifting may provide important data for shaping future policies," they conclude.
An addiction specialist, Volkow has been NIDA's director since 2003.