Medical marijuana: No proven clinical value | Miami Herald

In a recent poll conducted for the Miami Herald, 54 percent of the Miami-Dade County respondents said they support legalization of medical marijuana. Trailing not far behind, 46 percent opposed it — a surprisingly high number given the one-sided nature of the well-funded pro-legalization campaign that has dominated local discussion on the issue.

But while the voices of residents and legislators are being heard, one crucial group has been left out of a debate — the scientific community that is assessing marijuana’s efficacy as a medical treatment.

What does this community have to say about marijuana being sold at dispensaries before it is proven effective through the FDA’s drug approval process? According to a recent study by Yale Medical School published in the Journal of the American Medical Association in May, there are very real risks associated with treating marijuana as a medical treatment, including structural brain damage, an irreversible lowering of the IQ, respiratory damage and increased risk of psychotic disorders.

Furthermore, the report states “Medical marijuana differs significantly from other prescription medications. Evidence supporting its efficacy . . . relies largely on testimonials instead of adequately powered, double-blind, placebo-controlled randomized clinical trials . . . and in general falls short of the standards required for approval of other drugs by the US Food and Drug Administration (FDA).”

Miami-Dade’s residents and legislators invariably hear that marijuana dispensaries are compassionate services for those afflicted by such serious diseases as cancer or HIV/AIDS, for whom it is said no other “medicine” suffices, justifying their use of an intoxicating smoked weed.

However, only 3 percent of those using marijuana dispensaries suffer from cancer or HIV/AIDS, according to a recent RAND study that examined participants in California.

Who actually uses these facilities? Participants in the study found them to be overwhelmingly male (73 percent), substantially unemployed (31 percent), largely reporting “chronic pain” (58 percent) as their medical condition (nearly half of them already having a prescription for opiates), with another 44 percent reporting either a mental or sleep disorder as their reason for needing marijuana.

To date, there is no compelling clinical need for what smoked marijuana purports to do; the medical conditions for which it might be applied are already treated by non-marijuana medicines that have been found safe, effective and without risk of abuse.

The risk to young people is great, and scientific evidence continues to mount. A recent study in the New England Journal of Medicine by the director of the National Institute of Drug Abuse sums up the known adverse effects of marijuana smoking, with considerable stress on the dangers of adolescent exposure.

Modern medicines are a product of medical research, using scientific methods. Medicines are not made by agenda-driven legislators or well-meaning crowds by a show of hands.

Medicine is not wish-fulfillment, able to turn an intoxicating folk-remedy into a healthy medical compound by clicking ones’ heels. Medicine is determined by controlled results. Most importantly, when it comes to acceptance, science has the only vote that matters.

Marijuana is a Schedule I Controlled Substance — a dangerous substance with no recognized medical use — for a reason. It has not completed the course of proof required of all legal medicines sold in the United States. Until rigorous clinical trials can demonstrate therapeutic efficacy sufficient to outweigh its risks, marijuana will remain such, as the FDA reiterated in 2006. Let the research go forward, but not by abandoning standards.

David Murray was chief scientist at the White House, Office of National Drug Control Policy and is a senior fellow at the Hudson Institute’s Center for Substance Abuse Policy Research.