Incorporating herbs into meds education

How much information is just right?

Although herbal supplements are extremely popular, they are not always safe. Consumers need to know that taking ginseng, echinacea, and St. John’s wort is not the same as taking a multivitamin in the morning.

Herbs, which are parts of a plant such as the flower, seed, or stem, are an alternative form of drug. Therefore, they can interfere with other medications, have adverse interactions with food, can cause a medical problem to occur, or worsen an existing condition, says Ann Nawarskas, PharmD, PA-C, a clinical specialist at the New Mexico Veterans Affairs (VA) Health Care System in Albuquerque.

"I have had patients with borderline blood pressure problems who take licorice or supplements with licorice that cause their blood pressure to get worse," says Nawarskas. Before taking herbal supplements, patients need to consider their medical conditions, past surgical procedures, drugs they are taking, and dietary restrictions. 

They also need to have a clear understanding of what the herb will do. Although The Ohio State University Medical Center in Columbus does not provide patient education monographs on specific herbs and dietary supplements, the drug information center will provide specific information when patients or health care providers request it, says Marva Tschampel, RPh, a drug information pharmacist in the department of pharmacy. Information on supplements is not routinely made available to patients because it might encourage the use of herbs without scientific justification, she says.

When a request is made for information on an herbal supplement, Tschampel’s favorite reference is the Natural Medicines Comprehensive Database, Fourth Edition, published by Therapeutic Research Faculty in Stockton, CA. This reference is available in hard copy and on the web at

It has a standardized format, which includes synonyms, scientific names, possible uses, safety, effectiveness, mechanism of action, adverse reactions, interactions with herbs and other dietary supplements, interactions with drugs, interactions with foods, interactions with lab tests, interactions with diseases or conditions, dosage, and administration.

Communicate with the physician

"A general statement of the use of herbs and dietary supplements is provided to patients to encourage their communication with their doctors and nurses," says Tschampel. People always should discuss the herbal supplement with their health care provider before taking it, agrees Nawarskas. She recommends that people create a list of the current medications that they are on that include over-the-counter purchases as well as prescriptive medicines whether taken infrequently or regularly.

It’s important for patients to discuss herbal supplements with their providers because there are potential herb-disease interactions, drug-herb interactions and herbal-food interactions that should be screened for, says Nawarskas. For example, St. John’s wort can decrease the blood thinning effect of warfarin, which is prescribed to keep blood clots from forming. It also can reduce the effectiveness of some HIV drugs. "The herb increases the risk of developing drug resistance so the virus is no longer sensitive to the HIV medicine," she says.

Another important issue for patients to remember is that they may have an adverse or allergic reaction to herbal supplements. "People don’t have to take herbs in large doses or long-term to have problems. In the last six months to a year, there has been more and more in the press about kava, which is used as a sleep agent and for anxiety. There have been reports of individuals who have gone into liver failure while taking it," says Nawarskas.

People who purchase herbal supplements need to know that there is no guarantee that the contents listed on a label are actually contained in the bottle. "In the United States, there are no laws that require any of the herbal supplement manufacturers to prove that their advertised product contains a certain amount of the ingredients advertised," she reports.

Many factors can influence the product. The strength, purity, and effectiveness of a product depend on where the herb was grown, how it was stored, and how it was manufactured. An herb in a product may have been mixed with another crop or there may be only a trace of the herb in the product. Sometimes the product doesn’t even contain the herb, says Nawarskas.

To make sure they are purchasing a quality product, consumers should look for the seal of approval from two agencies that offer verification programs for herbal products. These include the United States Pharmacopoeia (USP), based in Rockville, MD, and the National Nutritional Foods Association (NNFA) in Newport Beach, CA, working with NSF Inter-national in Ann Arbor, MI. These agencies test products to determine if they contain the herb on their labels and do random searches for quality assurance. However, only the companies that volunteer and pay a fee for this surveillance are monitored.

Participating manufacturers who are approved by the USP will have the dietary supplement verification program mark on the container label. Those approved by NNFA will have the good manufacturing practice seal of approval on the label.

While patients need to be educated about herbal supplements and how to use them safely, health care providers also need to be kept abreast of current information. Therefore, at The Ohio State University Medical Center, the Department of Pharmacy created a database for health care practitioners that can be accessed via the hospital intranet system. The database lists the adverse effects and drug interactions of a group of targeted herbal and dietary supplements that are selected on the basis of published articles in the medical literature, says Tschampel.

"Included in the patient history are questions regarding the use of herbs and dietary supplements. This list is matched to the database for potential adverse effects or drug interactions," says Tschampel.


For more information about educating patients about herbal supplements, contact:

  • Ann Nawarskas, PharmD, PA-C, Clinical Specialist, New Mexico VA Health Care System, 1501 San Pedro Drive, S.E., Mailbox 119, Albuquerque, NM 87108. Telephone: (505) 265-1711, ext. 5948. E-mail:
  • Marva Tschampel, RPh, Drug Information Pharmacist, Department of Pharmacy, The Ohio State University Medical Center, 410 W. 10th Ave., 368 Doan, Columbus, OH 43210. Telephone: (614) 293-8679. E-mail:
  • National Nutritional Foods Association, 3931 MacArthur Blvd., Suite 101, Newport Beach, CA 92660-3013. Telephone: (800) 966-6632 or (949) 622-6272. Web site:
  • NSF International, P.O. Box 13140, 789 W. Dixboro Road, Ann Arbor, MI 48113-0140. Telephone: (800) 673-6275 or (734)-769-8010. Web site:
  • U.S. Pharmacopoeia, 12601 Twinbrook Parkway, Rockville, MD 20852. Telephone: (800) 822-8772 or (301) 881-0666. Web site:
  • Natural Medicines Comprehensive Database, Fourth Edition, published by Therapeutic Research Faculty, 3120 W. March Lane, P.O. Box 8190, Stockton, CA 95208. Telephone: (209) 472-2244. Web site: