In a controversial new statement, the U.S. Food and Drug Administration (FDA) declares that there are no "sound scientific studies" showing that marijuana can be used medically. But critics have derided the statement as political, not scientific, the New York Times reported April 21.

An FDA spokesperson said the statement, issued at the request of Congressional lawmakers, was based on an interagency review involving federal drug enforcement, regulatory agencies, and researchers. The statement concluded that, "smoked marijuana has no currently accepted or proven medical use in the United States and is not an approved medical treatment."

However, the statement contradicted previous findings by the Institute of Medicine at the National Academy of Sciences, the nation's leading scientific advisory board, which in 1999 issued a detailed report that concluded that medical marijuana was "moderately well suited for particular conditions, such as chemotherapy-induced nausea and vomiting and AIDS wasting."

Critics also said that if sound studies of medical marijuana are lacking, it is because the federal government has repeatedly blocked researchers from conducting such studies. "The reason there's no good evidence is that they don't want an honest trial," said University of Massachusetts professor Lyle E. Craker, whose 2001 application to grow high-quality marijuana for research was denied by the Drug Enforcement Administration in 2004.

A spokesperson for the Office of National Drug Control Policy said the FDA statement would end "the bizarre public discussion" of medical marijuana, which has been legalized in 11 states. The FDA statement said those laws were "inconsistent with efforts to ensure that medications undergo the rigorous scientific scrutiny of the FDA approval process."

But the cochairman of the panel that issued the 1999 Institute of Medicine report said the FDA statement was flat wrong. John Benson, a professor of internal medicine at the University of Nebraska Medical Center, said the federal government "loves to ignore our report. They would rather it never happened."

"Unfortunately, this is yet another example of the FDA making pronouncements that seem to be driven more by ideology than by science," added Jerry Avorn, a medical professor at Harvard Medical School.