Beware the new age pharmaceuticals.

Have you noticed that the advertising industry is starting to sound like a L witch doctor? "Feeling forgetful? Take ginkgo biloba. Depressed? Try St. John's wort. Irritable? How about some kava kava?" There seems to be an herb for every possible complaint. You'd think there is no need to consult a doctor or a pharmacist--the shelves of every drugstore, grocery store, and health food store are lined with attractive little boxes and jars. Claims are in a euphemistic code like promotes healthy digestion, or sleep, or mood, or heart health, or sports performance, or a host of other ailments and remedies. All seem benign because they are "natural" and have taken their place in the mainstream health market, advertising in major publications and on network television. How on earth is the consumer supposed to know the good from the bad or the useless from the dangerous?

The problem is not necessarily that the claims are all false. In fact, many herbal remedies have been shown to be effective, relatively safe, and are supported by respectable research studies. The problem is more complicated (and potentially more dangerous) than the risk of wasting money on a useless "cure." The problem is that there is no gatekeeper who looks out for your welfare. Traditionally, your doctor carefully prescribes and monitors medications with the advantage of the Physician Desk Reference, the bible for drugs, which lists every side effect, potential complication, drug interaction, contraindication, and the chemistry of every prescription drug in existence. No such compendium exists for herbal remedies because there is a shortage of good research. And more importantly, even when the information is known, herbal preparations are available without a prescription or the advice of a professional.

As herbal remedies become more prevalent, interactions with other prescription drugs are being reported more often, and sometimes the consequences are serious. In a recent review of complications arising from drug-herb interactions from George Washington University, 21 commonly used herbal preparations were identified that produced significant drug interactions. Most complications occur because herbs can either increase or decrease the absorption of other medications. Siberian ginseng, for example, raised digoxin concentrations, which is used to treat congestive heart disease, while guar gum slowed digoxin absorption. St. John's wort reduced the concentration of cyclosporin, a powerful antibiotic, and reduced the effectiveness of oral contraceptives.

In addition to drug interactions, the review confirmed the misidentification, adulteration, and contamination of herbal products. This is the warning most often given regarding supplements. Because they are not regulated, you have no reliable way of knowing exactly what you are taking. Renal poisoning, encephalopathy, neuropathy, and newborn hormonal problems were the result of mistakes in the identification of herbs.

Often patients are reluctant to discuss their use of herbs and supplements, worrying that doctors won't agree or understand. The lesson from this review is to overcome any inhibition you may have and at least discuss the use of all over-the-counter supplements or medications you use with your doctor or pharmacist, especially if you are taking a prescription drug. Better safe than sick. (The Lancet, 2000, Vol. 355, pp. 134-138; pp. 1019-1 020)