Warns you to notify doctor if you think you had it
　　MONDAY, April 16 (HealthScout) -- The United States government has stepped up its warning about aristolochic acids, plant extracts linked to permanent kidney damage and urinary tract cancers, and are now urging people to avoid products that might be contaminated with the substances.
　　The Food and Drug Administration is calling on consumers to immediately cease using products that might contain the extracts, found chiefly in "traditional medicines" and diet aids. The agency also says people who've used these products, or who suspect they may have, should contact their doctor.

"FDA advises consumers who have taken any of these products of concern to contact their health care provider immediately," the latest alert says. "Even if these products have not been used recently, consumers should still inform their health-care provider about which product they took, so that an appropriate evaluation may be conducted."

Earlier this month, officials called on supplement makers to police their products more closely to make sure they're free of aristolochic acids. The FDA also asked manufacturers to monitor and report adverse reactions to their products to the agency.

Symptoms may show too late

Heavy doses of aristolochic acid can cause immediate harm, but people who take small amounts may not develop symptoms until serious organ damage has set in, officials say.

Last spring, FDA officials cautioned health-care professionals about the compounds after two people in the United Kingdom were found to have developed kidney failure after taking products containing them. And in the early 1990s in Belgium, more than 100 cases of kidney damage were traced to a dietary supplement containing aristolochic acids, the FDA says. At least 70 of those patients needed kidney transplants or dialysis.

Those incidents led the agency to impose an import ban on supplements likely to consist of aristolochic acids.

A study last year in the New England Journal of Medicine showed a high rate of urothelial carcinoma, a form of urinary tract cancer, in people who used Chinese remedies with the compound. Similar cases have occurred in France.

Officials say at least two people in the United States have been diagnosed with end-stage kidney disease associated with supplements containing aristolochic acid.

The agency last year conducted tests on nearly three dozen supplements labeled as having Aristolochia spp. Eighteen of the 34 products contained aristolochic acids, officials say. A number of companies have recalled specific batches of products that were found to have the compounds.

Officials acknowledge that determining which items are at risk of being tainted with the toxin is tricky. Three ingredients, "Aristolochia," "Bragantia" and "Asarum" may be contaminated with aristolochic acids, the FDA says. But at least 14 forms of the toxin are known to exist and the plant family they come from has roughly 600 members, so any list is far from comprehensive, officials say.

Other ingredients that may contain the substances include: Aristolochia spp., Asarum spp., Bragantia spp., Stephania spp., Clematis spp., Akebia spp., Cocculus spp., Diploclisia spp., Menispernum spp., Sinomenium spp., Mu tong, Fang ji, Guang fang ji, Fang chi, Kan-Mokutsu, and Mokutsu.

In addition, supplements that may also contain aristolochic acid ingredients include Dutchman's pipe, birthwort and wild ginger.

Barbara Mitchell, executive director of the Acupuncture and Oriental Medicine Alliance in Olalla, Wash., says her group has notified its 12,000 members about the FDA's warnings, and is encouraging them to be more vigilant about whether their treatments are tainted with aristolochic acid.

"When ordering herbs we recommend that our folks ask their suppliers to ensure that they or the manufacturer have done an FDA-approved test," Mitchell says. The agency requires that herbs be certified "free" of the chemicals, but they can contain up to 0.5 parts per million of the compounds and still meet that standard, she says.
　　
　　From healthScout