Lancet Questions FDA's AER System for Supplements

WASHINGTON--Associations between adverse events and dietary supplements are difficult to verify, and more research into the hazards of these products should be a priority, according to researchers publishing in the Jan. 11 issue of The Lancet (361:101-6, 2003). Mary E. Palmer, M.D., et al worked with 11 poison control centers across the United States in 1998 to record details about ingestion of dietary supplements that caused adverse events.

"Drawbacks to the system of surveillance of adverse events associated with dietary supplements are cause for concern," Palmer et al wrote in the introduction. "Adverse events associated with dietary supplements are recorded only through voluntary reporting, which is an inherently weak form of surveillance." During the study period, the researchers recorded 2,332 calls about 1,466 ingestions; 36 percent of the ingestions were unintentional. Of the total amount, 159 calls were about gamma-hydroxybutyrate (GHB), which is no longer legally sold as a dietary supplement. The researchers determined 489 cases in which they were at least 60-percent certain that the negative events reported were associated with dietary supplements.

Reportedly, between 28 percent and 35 percent of callers took a dietary supplement to treat a disease, including benign prostate hypertrophy or anxiety. Other reasons for taking products included dieting, athletic performance and suicide attempts. The researchers noted the study had several limitations, including different practices at poison control centers and poor follow-up testing of products to determine actual ingredients. However, they concluded that some dietary supplements have potential for hazard and "raise issues about the regulatory and practical distinction between dietary supplements and drugs." Among their suggestions are mandatory registration of dietary supplement products and reporting of adverse events, defining what is a risk to safety, and determining when a recall is necessary.

Some of these concerns are already being addressed; the Bioterrorism Preparedness Act will require all food producers (including those of dietary supplements) to register with the Food and Drug Administration (FDA) by December 2003. FDA is also revamping its adverse events reporting system; the new system (CAERS) is due to come online this year.