How could marijuana legalization affect teens?

The American Academy of Pediatrics issued on Monday a new policy statement on marijuana that covers in detail many issues about marijuana in regard to adolescents and children. Unfortunately, the overwhelming theme of this new statement is, "We don't know."

The AAP engages in discussion of several important points. 1. Does decriminalization and/or legalization of marijuana and its component parts result in increased use by children and adolescents? 2. Is marijuana safe for children and adolescents? 3. Is marijuana ever a useful medicine for children and adolescents?

We do not know if decriminalization results in increased use by children or by adults. In countries where the law has changed, a slight increase has been seen among local residents, but "drug tourism" has markedly confused the issue as best demonstrated in the Netherlands and their experience over the last 25 years. Though the Dutch did not see a great deal of increase among their own citizens, they saw a huge increase in outsiders, leading to a disruption of local peace and quiet. This influx resulted in the passage of many subsequent laws to try to prevent the use of Dutch marijuana by people who were not citizens of the Netherlands. Early statistics from Colorado show that legalized marijuana has not been the gold mine that everyone worried about and that sales, if anything, are far below expectations. A long term view of the amount of legalized marijuana sales will be needed before anyone can make a definitive statement.

Before legalization/decriminalization, the use of marijuana among teenagers has decreased in the United States over the last 20 years by about 30 percent in casual use (use once a month or less), but has increased about 25 percent in daily use from about 1 in 30 teenagers using marijuana on a daily basis to about 1 in 20. It is not clear that legalization will make marijuana any more available to these teenagers. We do know that taxation and raising the price at which cigarettes and liquor are available has been an effective way of decreasing use of both among adolescents. Making marijuana available, but expensive may be a useful strategy.

There is also good data that for most adolescents, the initial use of marijuana is a not an altogether pleasant experience and that frequent marijuana use is often associated with "learning" how to appreciate marijuana's effects as part of joining a "cool" sub-culture. Thus, general cultural approval and sub-group approval of the use of marijuana is probably more important in terms of its widespread use than just its availability.

Regarding safety, the AAP reports that smoking marijuana is never safe for children or adults. The tars and other volatile products are clearly dangerous and can cause cancer in the same way that cigarette smoke can. There is limited data on whether use in either water smoking or oral ingestion is safe either. There are more than 200 neuroactive chemicals found in marijuana. Even the percentage of THC (tetrahydrocannabinol), which is the primary neuroactive compound, varies in marijuana by a factor of 30 times. Therefore, marijuana is not a consistent product and hard to make general statements about. We do know that the active products in marijuana change the adolescent makeup of the brain with decreases in white matter and increases in grey matter.  Marijuana is also fat-soluble and can stay in the brain for a prolonged period of time (days to weeks). So pediatricians are worried about mothers using marijuana while pregnant or breast feeding and we are very worried about the long-term use of marijuana in developing brains (your brain grows and changes until about the mid-twenties).

How about marijuana as medicine? Unfortunately, there have been no good, controlled studies on the use of marijuana for medical purposes in children. Medicalized marijuana products have been shown to be useful in several instances in adults: 1. In relieving the nausea associated with anti-cancer drugs, 2. In alleviating anorexia in HIV patients, caused either by the disease itself, or by the anti-viral agents used to fight the infection, 3. In limited cases, as an anti-anxiety agent. None of these uses have ever been tested or have published data in children. Also, we do not know if these neuroactive compounds are safe either short or long term.

Also, marijuana is being used for many untested medical needs.  Many parents of children with uncontrolled seizure disorders are using marijuana derived products, but the effectiveness of this is simply not been shown.

The AAP does a great job of summarizing what we know, but we simply do not know much about the potential effects of legalization. The AAP did recommend that marijuana be decriminalized, so that penalties for marijuana-related offenses are reduced to lesser criminal charges or civil penalties, and reaffirmed its opposition to legalizing marijuana because of its potential harm on the developing brains of children and teens. Adolescents need to know about these potential dangers and we should also discourage women from using marijuana during pregnancy and while breast feeding.

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