Letters to the Editor

Health effects of marijuana a concern for some

The United States Centers for Disease Control and Prevention, among other organizations, is urging pregnant women and adolescents not to take marijuana. There are some who pooh-pooh this advice, and this may lead to serious untoward consequences.

It may come as a surprise to many, but mice and rats are very important participants in determining potential good or possible serious effects of the medicines we use. Indeed, their biologic and physiologic responses to drugs predict with a high confidence factor how these drugs will act in humans.

The importance of this cannot be overstated. Research performed at the Auburn University Harrison School of Pharmacy reveals effects on pregnant mice given THC, the active ingredient in marijuana. The fetus may seem normal at birth but has “long-lasting effects on learning and memory” and this can continue throughout adolescence. While this has not yet been studied in humans, there is no reason not to be concerned that results will be similar to that involving the rodents.

Meanwhile, there are human studies of marijuana use by adolescents which have shown actual changes in the structure of the brain. These studies are still going on and, unfortunately, results will not be available for several years.

The concern, however, is also based on the more recent recognition that the adolescent brain is not yet mature, and any drug (and marijuana is a drug) can potentially affect final maturation. Furthermore, it is now understood that brain maturity is not reached until about the mid-20’s.

This is not an example of regulatory agencies being overzealous. The science is providing worrisome signals that should be given careful consideration.

W. J. Blechman,

Miami

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