Health Canada Reports on Adverse Events, Herbs

OTTAWA--In its quarterly publication of alerts to health care professionals, Health Canada reported the adverse events recorded for echinacea, Ginkgo biloba and St. Johns wort over the past five years. These three herbs, according to the agency, were chosen because they are the countrys most popular herbal remedies. The advisory was created to help health professionals assess the risk-benefit ratio of health care products, which includes pharmaceuticals.

In a search of its database for the period between Jan. 1, 1998, and June 30, 2003, Health Canada (www.hc-sc.gc.ca/English) reported echinacea was linked to 23 reports of suspected adverse events, ginkgo to 21 reports and St. Johns wort to 45 reports. In the case of echinacea, four cases were due to allergic reactions. Ginkgo was linked to a fatal gastrointestinal hemorrhage and a stroke (where the patients were also taking multiple concomitant medications). For St. Johns wort, the most common reports involved central and peripheral nervous system disorders and psychiatric disorders, including two cases of mania (in the mania cases, patients were also taking pharmaceuticals).

In Canada, as in the United States, when an adverse event is filed for a supplement containing two or more ingredients, the event is noted for all ingredients individually