By Stephen Sidney, M.D. and Bruce Mirken

All Americans, whether or not they have any interest in medical marijuana, should be concerned by the Food and Drug Administration's recent statement claiming there is no evidence that marijuana is medically beneficial. The FDA's pronouncement tells us little about medical marijuana, but it says much about how politics appears to be trumping science at the agency we all depend on to protect our health.

The FDA's missive, issued late in the day on April 20, proclaims that "no sound scientific studies" support medical use of marijuana, and condemns state medical marijuana laws.

But why, one wonders, did the FDA issue this statement now? It cites neither new scientific data, nor even any new analysis of old data. The FDA did not, as it often does when addressing difficult issues, convene an advisory committee of independent experts. Indeed, the document appears to be nothing but a rehash of the federal government's longstanding position.

And it's a selective rehash, to put it gently. Back in 1995, the American Public Health Association cited nearly two dozen studies reporting marijuana's safety and efficacy against pain, nausea, vomiting, seizures and other serious symptoms. The APHA urged the government to "expeditiously" make marijuana available to patients through the Compassionate Investigational New Drug program that the first Bush administration had closed to new applicants in 1991, declaring, "Greater harm is caused by the legal consequences of [marijuana's] prohibition than possible risks of medicinal use."

Four years later, in a massive review commissioned by the White House, the Institute of Medicine (a branch of the National Academy of Sciences) found significant evidence of therapeutic benefit, stating: "Nausea, appetite loss, pain and anxiety are all afflictions of wasting, and all can be mitigated by marijuana." While expressing concern over the risks of smoking, it noted that for some patients -- particularly those with terminal conditions or not responding to standard therapies -- those risks would be "of little consequence." The IOM report added pointedly, "We acknowledge that there is no clear alternative for people suffering from chronic conditions that might be relieved by smoking marijuana, such as pain or AIDS wasting."

The FDA simply ignored this mass of data. Indeed, the federal government has long been hiding from such information. As Dr. John Benson, one of three lead authors of the IOM report, told the New York Times last week, the government "loves to ignore our report. ... They would rather it never happened."

It is true that the volume of research data on medical marijuana is not as great as any of us would like. But the relative lack of large, controlled trials of marijuana is almost entirely due to government obstructionism.

The federal government has not only refused to fund medical marijuana research, it has put in place a set of legal and bureaucratic obstacles that have kept the flow of even privately-funded medical marijuana studies to a trickle. So with one hand, our government tells us "there's no data," while with the other hand it works to ensure there will never be enough data.

So why did the FDA issue this questionable document, containing no new information whatever, at this particular moment? The only apparent explanation is politics. Rep. Mark Souder (R-IN), perhaps the most vehement opponent of medical marijuana in the U.S. Congress, has been hectoring the agency for months to issue a statement condemning medical marijuana.

On January 18, Souder wrote to acting FDA Commissioner Andrew C. von Eschenbach, "I am exasperated at FDA's failure to act against the fraudulent claims of 'medical marijuana." He renewed the request two months later, in even more impatient terms. And Souder's agenda fit perfectly with the administration's stand on the issue, so all the political winds were blowing in the same direction. Science, it appears, took a back seat.

For the FDA to do its job as protector of our nation's health, it must be free from commercial or political pressure. When politics trumps science at the FDA, we are all in danger.

Stephen Sidney, M.D., is associate director for clinical research for Kaiser Permanente's Division of Research in Oakland, California. His opinion reflects his personal views and not those of the Kaiser Permanente Medical Group. Bruce Mirken is director of communications for the Marijuana Policy Project, www.mpp.org.