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Aug. 9, 2000 (Washington) -- The FDA's attempt to impose stricter regulations on the herb ephedra, a common ingredient in many popular weight-loss regimens, may have to wait for another day.
The agency's efforts appeared in jeopardy once again Wednesday at the conclusion of a two-day public meeting, where it permitted interested parties to air their concerns prior to proceeding with the passage of proposed new regulations.
FDA officials claim that they have identified at least 17 instances of serious side effects that can be attributed to use of the herb, including one death, two heart attacks, and one seizure. However, the FDA interpretation of those cases came under considerable attack during the two-day meeting, which was primarily dominated by representatives of the ephedra industry.
For one, the FDA failed to demonstrate that the rates of adverse events associated with ephedra-containing products are higher than what one would expect to find in the general population, says Stephen Kimmel, MD, a research professor at the University of Pennsylvania, who spoke on behalf of ephedra makers. Moreover, the reports cited by the FDA did not contain enough information to draw any concrete conclusions that ephedra was the culprit, because the adverse events suffered also be could explained by other conditions the people had, he says.
These industry arguments are reminiscent of a 1997 dispute between agency officials and makers of ephedra, which eventually ended with the FDA withdrawing its proposed regulations for the drug. At that time, the FDA proposed a number of restrictions on the use of ephedra that a congressional audit later determined were not based on strong scientific evidence.
At question still is not whether ephedra causes any side effects, but rather whether these side effects truly are serious enough to merit the passage of stricter government regulations over the supplement. Makers of ephedra say the FDA's latest proposed rule goes way overboard, and in effect, would act as a ban on a product that not only offers a distinct public health benefit, but also meets a growing public demand for that benefit, namely weight loss.
Despite this ongoing heated debate between makers of ephedra products and U.S. regulatory authorities, the use of ephedra-containing products for weight loss has grown from less than 500,000 servings in 1993 to over 3 million in 1999. At the same time, consumer reports of adverse events have fallen and flattened to a level of just about 150 reports per year, or a little more than 1994 levels when about 750,000 servings were sold.
Under the FDA's proposed rule, makers of ephedra products would not be able to combine the herb with known stimulants, such as caffeine. The proposed rule also would establish a stricter warning label to highlight the potential for serious adverse events, such as heart attacks, strokes, and seizures.
For proponents of the herb, the most disturbing aspect to the proposed rule is the ban on its combination with known stimulants. More than half the ephedra-containing products on the market today are made with caffeine. However, ephedra's advocates point out that besides being based on anecdotal reports, the FDA's "risk analysis" also ignores the fact that these combination products are an effective treatment for obesity, one of the nation's leading health problems.
In contrast, the FDA's expert advisers maintain that there is not enough evidence to show that ephedra works well enough as a weight-loss drug to justify the risk. "This is not an issue of whether people will be killed or harmed. The question is whether there is a medical benefit to this risk," says Raymond Woosley, MD, director of pharmacology at Georgetown University, who reviewed a number of adverse events for agency officials.
If that indeed is the question, then the FDA may soon have additional headaches. Also speaking on behalf of ephedra makers at the meeting were researchers from Columbia and Harvard University, who indicated that they soon would release results from a placebo-controlled clinical trial that will demonstrate both the effectiveness and safety of the herb when used according to established guidelines.
At the very least, that is a good reason for the FDA to delay taking any action, proponents of ephedra now also argue. Echoing their successful rallying cry of 1997, not to review this additional evidence prior to making a final decision, would in fact be plain "bad science," say people such as William Soller, PhD, senior vice president for the Consumer Healthcare Productions Association, an industry association.
Those types of arguments do not bode well for the FDA, which is trying to pass its proposed new regulations without giving the dietary supplement industry or public the impression that it is biased against dietary supplements in general, and ephedra in particular
Still, use of ephedra continues to be a serious public health concern, maintain FDA officials such as Lori Love, MD, PhD, whose opinion is shared by a number of her colleagues. But if the FDA wants to establish a consensus, it still has a long way to go with the general public, those of which seem oblivious to the regulator's concerns.