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April 20, 2000 -- Many makers of dietary supplements containing ephedra are selling products containing significantly less -- or much more -- ephedra than stated on the label, according to a new study published in the American Journal of Health-System Pharmacy. Now the question facing the manufacturers is whether they're being purposefully deceitful or just careless.
"It could be both," study co-author William J. Gurley, PhD, tells WebMD. Gurley is an associate professor in the department of pharmaceutical sciences in the College of Pharmacy at the University of Arkansas for Medical Sciences.
Critics of ephedra's use as a dietary supplement point out that the active ingredient of this Asian herb is ephedrine, a stimulant that acts similarly to amphetamines. The American Council on Science and Health reports that serious effects of ephedrine-based products have been linked to psychosis, seizure, heart attack, stroke, and even death.
Just this week, 24-year-old Sarah Ingram, who wanted to lose 10 pounds before her wedding, now lies in a Virginia hospital after suffering a stroke that has paralyzed her right arm and left her unable to speak or understand language.
"At this point I have no other reason to suspect anything else except ephedra use," says Michael Hoffstetter, MD, a neurologist and Ingram's attending physician at Prince William Hospital in Manassas, Va. He tells WebMD it's extremely unusual for someone this young to have a stroke like this -- the odds are about 3.5 per 100,000 people. "Her family has no history of stroke and she has no history of high cholesterol, high blood pressure, or diabetes," he says.
Some people taking the supplement may be getting even more than they bargained for, according to the new study. In it, researchers analyzed 20 different ephedra-containing products purchased in 1999 from retailers or via the Internet. Two separate lots of 10 of the products were compared and analyzed for ephedra content. Researchers discovered half of the products exhibited discrepancies of at least 20%. Some even had 154% more ephedra than the amount claimed on the label. One product had no ephedra at all. Researchers frequently even found inconsistencies between groups of the same product.
The FDA is now gearing up for a new assault on the supplements. It notified Congress on Feb. 25 that it is launching a new push to address public safety issues posed by ephedra. To date, the FDA has produced 800 reports showing ephedrine-based supplements could produce a rapid or irregular heartbeat, increased blood pressure, anxiety, insomnia, hyperactivity, and tremors.
"There's a lot of concern about this particular product in terms of its safety," says Joe Levitt, who heads the FDA unit that oversees dietary supplements. "There is a public health issue here that needs to be addressed."
The 20 products examined in the study are only a fraction of the hundreds of dietary supplement products sold containing ephedra, which is derived from ma-huang and manufactured into capsules, liquids, and powders. Metabolift, manufactured by Ronkonkoma, N.Y.-based Twinlab, was the brand taken by Ingram. Although not part of the group of 20 in the study, Gurley told WebMD he has studied that particular product on a smaller scale. He found that the 10 mg of ephedra per capsule stated on the label was understated by 25%. So those taking the two capsules recommended would be receiving 25 mg rather than the 20 mg listed.
In a formal statement released in the fall of 1998, Theodore M. Farber, PhD, a longtime proponent of ephedra and an FDA critic, said, "The medical fact, confirmed by online medical literature and the absence of injury reports to the FDA on the ingestion of 25 mg doses of ephedrine by asthmatics, is that 25 mg of ephedrine per single dose has never shown any serious adverse effect on human beings being studied in over two dozen clinical trials."
Hoffstetter disagrees, based on his own observations. "I have other patients complain of excessive nervousness or had significant changes in blood pressure. Since ephedra hasn't undergone the scrutiny of other drugs, it's like the public is their clinical trials. I think the manufacturers of health supplements misrepresent the products. I think it's necessary for the FDA to step in and regulate these compounds."
Gurley doesn't take quite as strong a stand. "If you want to take these, go ahead. It's a free country. But people have a right to know how much they're taking."
Hoffstetter says readers who have questions about drug interactions with ephedra may e-mail him at drhoffstetter@aol.com.