While the pharmaceutical industry supports the proposal, many oppose it, including Consumers Union, the Blue Cross Blue Shield Association of health insurers, the federal government’s own Veterans Affairs Pharmacy Benefit Service and powerful congressional leaders on both sides of the aisle.

Even the American Medical Association suggests that the new rules would further undermine accurate and unbiased drug information, reflecting reports in its journal, JAMA, documenting industry manipulation of article content.

While most people assume that the medicines prescribed by U.S. doctors have the FDA’s stamp of approval, that’s only partially true. The FDA approves drugs for specific purposes, but doctors can use drugs “off-label” for medical conditions not approved.

Off-label prescribing is common, says Randall Stafford, MD, PhD, an associate professor of medicine at the Stanford Prevention Research Center. In an editorial in the April 3 issue of The New England Journal of Medicine, Stafford criticized the draft guidelines.

Unfortunately, says Stafford, what’s known about the use of a drug for one situation may not apply to other clinical scenarios. He points to the use of antidepressants in children and the use of antipsychotic medications for dementia as key examples.

“The FDA should not suddenly start telling physicians how to practice. Physician judgment is critical, especially when approved therapies have not succeeded,” he says. “But in other cases, off-label prescribing has become first-line therapy even in the absence of strong evidence of benefits and safety. This is problematic.”

Stafford says these types of situations suggest the need for a better way to evaluate and regulate off-label drug use. Ideally, he says, a drug company would go back to the FDA with additional clinical studies and obtain supplemental approval for a new clinical use.

Although regulations restrict drug manufacturers from overtly promoting their drugs for unapproved conditions, they are free to show physicians educational materials, most often published journal articles. According to current FDA guidelines, this practice is acceptable, but only if the manufacturer submits the articles to the agency for review and is pursuing formal approval for the new use. In reality, however, enforcement is limited, says Stafford.

The new draft guidelines further pull back federal involvement by eliminating both of these requirements. In addition, they reduce the remaining policies to non-binding recommendations.

One major pitfall of the proposed guidelines, says Stafford, is they would widen a loophole, letting drug manufacturers skip the approval step for additional, potentially more lucrative, drug uses. Instead, companies might seek approval only for a narrower use that’s more easily and less expensively tested, and sponsor research on more commercially promising uses that are never evaluated by the FDA. Stafford warns that this might encourage more physicians to treat with drugs never approved by the agency for those purposes.

Amid the continuing controversy, the FDA’s next step remains to be seen.