A Woman who has been taking a prescription for her high blood pressure was advised by a friend to see an herbalist, who sold her a bag full of remedies. Now, the woman admits, she knows almost nothing about those remedies. Nor has she told her doctor about them.
Are they safe? What drug effects do they have? And what side effects? Will they interact badly with her prescriptions and cause her blood pressure to plunge dangerously low? She doesn’t know, and, chances are, neither does her doctor.
The woman with high blood pressure is but one of many who wander blindly into the world of herbal remedies, a world that remains unregulated. The popularity of these products has soared. In 2001 alone, Americans spent $4.2 billion on herbs and other botanical remedies.
Herbal remedies don’t have to meet the standards of safety and purity specified in the Federal Food, Drug and Cosmetic Act. The same applies to vitamins and minerals sold as dietary supplements. And, none of them have to be tested to define their medicinal effects.
This is not to say that all these remedies are unsafe, impure or ineffective. Some are made by reputable companies under near-pharmaceutical conditions. Some have been tested in well-designed clinical trials. Still, the consumer has no way to know exactly what is in the bottle and what effects the contents may have on health.
Kava, long popular for its antianxiety effects, was ultimately found to be toxic to the liver, sometimes damaging it to the point that a transplant is needed. Aristolochia plants have been used for centuries, Dr Peter A. G. M. De Smet of Netherlands noted, but their ability to cause urothelial cancer has only recently become clear.
Not long ago, nearly half of all prescription drugs were derived from plants or synthesised to mimic a plant chemical. Clearly, plants contain thousands of ingredients with drug effects.
In his journal review, Dr. De Smet notes that while ginkgo leaf extracts have been promoted for the treatment of dementia, peripheral vascular disease and neurosensory problems like tinnitus, well-designed studies have shown mixed results. The herb may sometimes cause headaches, nausea, gastric symptoms, diarrhea or skin reactions.
Hawthorn appears to improve mild cases of heart failure; saw palmetto improves urinary symptoms in men with benign prostatic enlargement; St. John’s wort has helped to relieve mild to moderate depression; feverfew can help to prevent migraine headaches; and ginger can help counteract motion sickness and nausea in pregnancy.
To date, however, the data are inconclusive about the benefits of valerian to counter insomnia, echinacea to prevent and treat common colds and ginseng for any purpose. Until the regulation of herbal remedies improves, however, it is caveat emptor – let the buyer beware. ?
Jane E. Brody
New York Times