A New England Journal of Medicine Article about Marijuana

Senior members of the National Institute on Drug Abuse recently published an important paper about marijuana in the New England Journal of Medicine. Here are some sobering points:

The concentration of the active ingredient in marijuana has increased about 4-fold in the last 30 years. This means that today’s marijuana is much more potent than the marijuana available in the past.

Addiction to marijuana is 2 to 4 times more likely in those who start using the drug as adolescents than in those who start using as adults. About 1 in 6 teenagers who experiment with marijuana become addicted. This means that it is imperative to discourage young persons from initiating marijuana use. Younger age of first use predicts more problems.

“Both immediate exposure and long-term exposure to marijuana impair driving ability; marijuana is the illicit drug most frequently reported in connection with impaired driving and accidents, including fatal accidents.” While either alcohol consumption or marijuana use alone has adverse effects on driving, the combination is particularly dangerous. What happens when a young person who is stoned and has had a few drinks decides to text while driving?

The use of marijuana is associated with “measurable and long-lasting cognitive impairments, particularly among those who started to use marijuana in early adolescence.” Early use of marijuana has significant adverse effects on school performance and may have longer-term adverse effects on brain structure and function in adulthood.

Marijuana use is associated with increased risk of psychotic illness, especially in those genetically predisposed to such illnesses. The mechanisms underlying this association are under active investigation. Marijuana use is a significant risk for anyone who has either an existing psychiatric disorder or a predisposition to psychiatric illness.

To date, a small number of medical conditions respond to treatment with marijuana or marijuana-like drugs. With further study, it is likely that more disorders will be shown to benefit from careful use of marijuana-like drugs. As is true with any medicine, the potential benefits versus potential risks of such treatment must be considered. Much more research examining the medical conditions that respond to marijuana therapy is needed.

The information in this review article reinforces the importance of minimizing the use of marijuana by young people. The central nervous system continues to develop throughout adolescence, and marijuana can have strong, long lasting adverse effects on this development.

The article closes with the following statement: “As policy shifts toward legalization of marijuana, it is reasonable and probably prudent to hypothesize that its use will increase and that, by extension, so will the number of persons for whom there will be negative health consequences.”

Marijuana will generate considerable tax revenue for state governments. We hope that some of these funds will be set aside to cover the increased medical costs and social consequences of legalization.

This post was written by Eugene Rubin MD, PhD and Charles Zorumski MD.