Diet Supplement Causes Nearly 100 Hepatitis Cases

Although people who took the supplement started getting ill in May last year, the Food and Drug Administration did not learn of the cases until four months later, in September, when doctors reported a cluster of liver illnesses in Hawaii. USPLabs stopped selling the product in October. [10 Medical Myths that Just Won't Go Away]

Health officials suspect that a new ingredient called aegeline that was added to the supplement caused the illnesses, Cohen said. Because the FDA regulates supplements only after they come to market, companies are not required to prove that their products are safe and effective before marketing them.

"This really points to the fact that there's no safety testing … before a new ingredient shows up in a supplement in the United States," Cohen said. "Guess who's the experimental animal — the consumer."

Dangerous supplements are supposed to be identified and removed quickly, but this is often not the case, as demonstrated by the hepatitis outbreak, Cohen said. Doctors can report adverse events tied to dietary supplements through an online portal called MedWatch.

But in most cases, the FDA does not receive reports of the harmful effects of supplements, Cohen said. Those cases might be reported to a poison control center, which does not communicate with the FDA, or they might not get reported at all, he said.

"Dangerous supplements remain on store shelves for weeks, months or years" because the FDA has a fractured system for monitoring supplements, Cohen said.

He proposes that all dietary supplements should be registered, and information about the supplements and their ingredients should be incorporated into a database maintained by the FDA and poison centers.

Under this organization, if a person has an adverse reaction to a supplement, it would be reported to a response team made of up doctors, toxicologists, pharmacologists and chemists. The team would then investigate the case, report to the FDA and offer advice about treating the patient.

"In the situation where we know that some supplements out there may be dangerous, we'd better have a really good system" to detect them, Cohen said.

While improved monitoring of supplements is needed, it is not the ultimate solution, Cohen said. Congress should change the law regulating supplements to require that all supplement ingredients undergo safety testing before they come to market, he said.

"Until that happens, consumers and physicians cannot be assured that the pills, powders and potions labeled as dietary supplements are safe for human consumption," Cohen wrote in the April 3 issue of the New England Journal of Medicine.

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