Consumer's Guide to Herbal Supplements

Americans spend $2.5 billion a year on herbal supplements, a few of which have been proved beneficial. But because these products don't undergo the same U.S. Food and Drug Administration testing that prescription medicines do, some of these supplements could be unsafe.

"Herbal supplements might be sugar pills, or contaminated or adulterated and therefore dangerous," says Gary Elmer, Ph.D., professor of medicinal chemistry at the University of Washington School of Pharmacy. "Still, if reputable products are used properly, they may be milder and safer than prescription medications, with fewer side effects."

The following suggestions can help you choose and use herbal supplements wisely and safely.

Look at your life

Before you buy an herbal supplement, analyze your diet, exercise habits and mental attitude. "Many people would rather take a tablet than try to deal with lifestyle problems that affect their health," says Dr. Elmer.

Instead of a supplement, perhaps more sleep, more exercise, a reorganized schedule or a healthier diet would help you feel better.

If these remedies don't work, check with your health care provider or a pharmacist about the supplements you're considering. Be sure to tell the person you consult if you're pregnant, are breast-feeding, have diabetes or are taking heart or high blood pressure medication or a blood thinner. An herbal supplement may complicate your condition.

A licensed health professional, especially one trained in herbal medicine, can make sure the supplement you're considering doesn't interact with the medications you're taking or pose any other harm.

Do your homework

In Europe and Asia, health care providers have been routinely prescribing herbal supplements for decades, even centuries, and in Asia, for millennia. Public knowledge and use of herbs in the United States is less common for several reasons: easy availability of modern, scientifically based and effective medicine, and lack of clinical studies showing the effectiveness of a majority of available herbs and supplements.

The U.S. Pharmacopeia, a body of experts that sets standards for prescription and nonprescription drugs in this country, has developed fact sheets on various herbs including valerian, feverfew and St. John's wort. The information is based on published reports and clinical studies.

Until the research on herbs is more definitive, Dr. Elmer recommends you read about the risks and benefits of specific herbal supplements before you buy them.

Be aware

Keep these do's and don'ts in mind if you decide a particular herb is right for you after consulting a health professional:

• Buy a name brand. Name brands, which are manufactured by large companies, probably are safer than other brands. "Chances are, a large herbal-supplement manufacturer has a well-established quality-control program," Dr. Elmer says. "It can afford the equipment it takes to analyze bags of plant material that come into the warehouse and to analyze the final product." Remember that having a “name brand” does not guarantee that an herb is effective.

• Don't mix herbs. Taking more than one herbal product at a time may increase the risk of side effects. Taking an herb with a prescription medication should be avoided or at least discussed with your health care provider first. Many instances of dire or fatal side effects have been documented from herb-prescription interactions. 

• Check the expiration date. Herbal supplements don't last forever. If a supplement is on sale, its potency may be about to wane.

• Stop using an herb if you have a reaction to it.

• Be patient. "Herbal supplements may take longer to take effect than their conventional counterparts because they're often less potent than prescription drugs," says Dr. Elmer. "It can take several months to notice a difference in your health."

• Also remember that time alone can improve you condition without any benefit from the herb. Sometimes it is difficult to separate the benefits of time from those of ineffective herbs such as echinacea.