New York Times News Service
June 8, 2000
In a harsh example of the dangers of, doctors are reporting that a Chinese herb already linked to kidney failure may cause cancer as well.
The herb, Aristolochia fangchi, was given to patients at a weight-loss clinic in Belgium from 1990 to 1992, according to a report appearing Thursday in the New England Journal of Medicine.
By 1993 more than 100 had kidney damage, and so far more than 70 have needed transplants or dialysis. Now, substantial numbers are also developing cancers of the urinary tract.
Cases of kidney failure from this herb have also been reported in France, Britain, Spain, Japan and Taiwan. Dr. Christine Lewis, director of the office of nutritional products, labeling and dietary supplements at the Food and Drug Administration, said there had been no reports of Americans being harmed by taking Aristolochia.
She also said the FDA did not know how much of the herb might be on the market in this country.
But last month, the FDA sent letters to doctors and to the supplement industry, with a six-page list of herbal remedies known or suspected of containing Aristolochia. The agency urged manufacturers to test their products for the presence of the herb.
Within weeks, importation of the herb, including every item on the six-page list, will be banned, Lewis said.
Herbs, amino acids, vitamins and other supplements, a $15 billion industry, are largely unregulated. Unlike drugs, they do not have to be proved safe and effective before they are marketed, and no outside agency checks to make sure that the products contain the ingredients on the label.
Under the 1994 Supplement Health and Education Act, the FDA does not have the authority to take supplements off the market until they are proved dangerous.
The report in the journal describes 39 patients given transplants or dialysis at Erasme Hospital in Brussels, by a team led by Dr. Joelle L. Nortier. Eighteen of the 39 have also developed cancers of the urinary system. Nineteen others have abnormal cells in the urinary tract, possibly precancers.
Aristolochia was given to patients by mistake; doctors had prescribed another herb, but the product that patients received was later found to contain Aristolochia, possibly because of a manufacturing error.
Those who took the most were most likely to develop cancer. Aristolochia
contains compounds called aristolochic acids, which are known to damage
the kidneys and to cause cancer in lab rats. The herb was traditionally
used in Chinese medicine for a variety of ailments, but about 25 years
ago German researchers found it to be highly toxic, according to Dr. Varro
E. Tyler, an expert on herbal medicine at Purdue University.