Herbal Medicine Hazards

By Dr. Geoffrey Morris*

The popularity of medicinal herbs has increased tremendously since 1994, the year that Congress passed the Dietary Supplement Health and Education Act.

The law exempted dietary supplements from premarket safety evaluations that are required of prescription and over-the-counter medicines, as well as oversight of the herbs’ manufacturing. The intent was to keep products available to those who want to use them, because they may help reduce health-care expenses and prevent disease.

Several popular herbs do have beneficial effects on the body, and some scientific evidence exists to support these claims. Garlic may lower blood pressure and cholesterol; ginkgo may improve brain function in Alzheimer’s disease; St. John’s wort is useful for mild depression; and saw palmetto may reduce prostate size.

The mislabeling of some herbs causes concern, because some have contaminants in them. A scientific analysis of 54 ginseng products found 25 percent contained no ginseng and 60 percent had trace amounts, while added caffeine varied from 10 to 90 percent. Plantain has been found to be contaminated with digitalis, which can cause heart block and death.

In the late 1980s a sleep-promoting compound called L-tryptophan was contaminated with a toxic substance that caused more than 5,000 people to develop Eosinophilia Myalgia Syndrome, a chronic illness similar to lupus, from which most have not recovered.

A tenet of the practice of medicine is premum non-secere — "first do no harm."

Unfortunately, some herbal manufacturers adhere to caveat emptor — "let the buyer beware."