Bitter orange: FDA called upon to ban ephedra substitutes.
A compound present in Citrus aurantium, synephrine, is chemically similar to ephedrine and may pose the same risks--a concern that has prompted one member of Congress to call on the Food and Drug Administration to ban the supplements.
Sen. Charles E. Schumer (D-N.Y.) has sent a strongly worded letter to FDA Commissioner Mark B. McClellan requesting immediate action for the removal of these products from the market, citing urgent safety concerns.
"It took the FDA more than 8 years to go from warning people that ephedra is dangerous to actually banning it. In that time, at least 155 people died from it," Sen. Schumer said in a statement. In contrast, he said, "it took the National Football League less than 3 months to ban ephedra after the Minnesota Vikings' Korey Stringer tragically died from it at training camp."
Synephrine is an [alpha]-adrenergic agonist that, like ephedrine, can cause vasoconstriction and increase pulse rate and blood pressure.
The hazards of bitter orange go beyond the ephedra-like stimulant effects, according to Dr. Sidney Wolfe, director of Public Citizen's Health Research Group. This fruit--a centuries-old component of traditional Chinese medicine known as zhi shi--also contains compounds that interfere with drug metabolism.
Like grapefruit juice, bitter orange contains compounds that inhibit the cytochrome P450 system, through which many drugs are cleared. "This introduces a whole new set of problems aside from the stimulant effects," Dr. Wolfe told this newspaper. "We certainly would not recommend that anyone use this."
Claims of efficacy for weight loss rest on one small industry-funded study. In that study, 20 patients were randomized to one of three groups: treatment with a supplement containing 975 mg C. aurantium, 528 mg caffeine, and 900 mg St. John's wort; a maltodextrin placebo; or no treatment other than the diet and exercise regimen followed by all participants. After 6 weeks, the active treatment group (n=9) lost 1.4 kg weight, which was significantly more than patients in the placebo and no treatment groups (Curr. Ther. Res. 60 :145-53, 1999).
"Certainly that study was by no means definitive," said Dr. Stephen Bent of the University of California, San Francisco, and the San Francisco Veterans Affairs Medical Center. "It really is quite amazing that this product is being marketed as a weight loss aid with no evidence to suggest that it actually causes weight loss," Dr. Bent said. "Bitter orange poses the same risks of stroke, MI, and death that are believed to occur with ephedra, and until it is studied more carefully, it should be avoided."
A further safety concern is that some bitter orange-based products also contain caffeine. "The combination of ephedrine and caffeine, which was in a lot of over-the-counter weight loss products, was banned in 1983," Dr. Donald Marcus said in an interview.
"We've known for a long time that ephedrine and caffeine are dangerous together, and it's ironic that you can sell a similar product if you call it a dietary supplement but not as a drug when it has the same dangers," said Dr. Marcus, professor of medicine at Baylor College of Medicine, Houston. He blames the Dietary Supplement Health and Education Act of 1994 (DSHEA) for this situation.
"DSHEA created a catch-22. On the one hand, it took away any requirement for manufacturers to maintain records of serious adverse events, while on the other hand it mandated a high standard of proof for the FDA to be able to remove products from the market," he said.
BY NANCY WALSH
New York Bureau
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|Title Annotation:||Clinical Rounds|
|Publication:||OB GYN News|
|Date:||Apr 1, 2004|
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