Personally, I believe the short answer is "yes", but it's not quite that straightforward…
Herbal remedies can be purchased at supermarkets, drugstores, and regular retail outlets, even Costco and Sam's Club. They are sold like any other over-the-counter (OTC) product, no differently than Tylenol™ or Sudafed™. This may explain why, in 1997, 60 million adults, nearly one-third of the U.S. population, each spent an average of $54 on herbal remedies. According to the National Business Journal, the total value of all herbal products sold in the United States in 1998 was expected to exceed $4 billion, more than twice what it was just two years ago.
Mostly, herbal drugs are used to treat minor medical problems like colds and allergies. They are also taken in hope of preventing illness from occurring. Increasingly, they are being taken with the goal of preventing heart attack, strengthening the immune system, promoting feelings of well-being, and preventing the effects of aging. In that sense, herbal remedies are very much like medicines prescribed by your doctor. But there are very important differences between the drugs your doctor prescribes and the herbal products sold in the grocery store. Prescriptions and OTC medicines are strictly regulated by the federal government. Herbal products are not.
When your doctor writes a prescription, you can be reasonably sure that (1) the medicine prescribed is appropriate for the condition being treated; (2) the makers of that particular drug have proven to the government's satisfaction that, in recommended doses, the drug is safe and effective; (3) except for inert binders and fillers, there is nothing else in the prescription except the prescribed drug; (4) when the prescription is refilled, it will contain exactly the same amount of the same drug as the first prescription; and (5) potentially dangerous drug interactions will be clearly stated on the package insert.
Users of herbal products lack these assurances. Recommendations posted on Internet bulletin boards do not carry the weight of large, multi-center, controlled clinical trials. Treatments recommended on the Internet, or in popular magazines, or by friends at work, may or may not be appropriate for your medical problem. Manufacturers of herbal products are not subject to the same regulations as manufacturers of prescription drugs, and if you are not buying from a large, ethical, manufacturer, you may find yourself getting both more and less than you paid for. For instance, a study conducted in 1978 found more than one-third of the commercial ginseng samples tested contained no ginseng. In 1998, a similar study of St. John's Wort-containing products, undertaken by investigative reporters at the Los Angeles Times, disclosed that one-third of the products tested contained less than half the amount of the product listed on the label!
The problem is not just truth-in-advertising. Compared to prescription drugs, the pathology and toxicology of herbal products have been poorly studied. Ginkgo Biloba may help treat depression and improve concentration, but it can also interfere with the way blood normally clots. The clerk at the check-out counter will almost certainly not know about this possible complication, and the label is equally unlikely to contain that bit of information.