How Long Before Herbs Are Regulated?
by Gary Snodgrass, Pharm.D.| Geriatric Times |  |
November/December 2000 | |
Vol. I | |
Issue 4 |
I opened my mailbox recently to be treated to a 15-page newspaper advertisement entitled "U.S. Health." The goal was to sell copies of a book on "natural medicines," and the approach was high-pressured and sensationalistic. Headlines screamed: "True Arthritis Reversal" and "Depressed Brains Feel Sunny Again." I began to wonder how I missed all this stuff in pharmacy school. All kidding aside, I began to worry about how the positive aspects of herbal medicines are being twisted and exaggerated.
Therefore, the goal for this edition of "Pharmaceutical Update" will be to examine if the current distinction between herbs and drugs makes sense and to try to assign some clinical significance to the current utilization of herbs by our patients.
As a clinical practitioner-whether you are a nurse, pharmacist or physician-what do you personally think of herbs? Are they medicines? For purposes of regulation, the U.S. Food and Drug Administration does not think they are. Herbs are lumped in with a variety of proprietary products as dietary aids or nutritional supplements. Manufacturers of these products are not subjected to the same FDA scrutiny as pharmaceutical companies. Consumers are not afforded the same protections that are mandated when an entity is classified as a drug.
How much sense does it make to pretend that herbs are not drugs? Merriam Webster's Collegiate Dictionary, 10th Ed., defines a drug as "a substance used as a medication or in the preparation of medication." Similarly, Webster's considers an herb to be "a plant or plant part valued for its medicinal, savory, or aromatic qualities." It is obvious that not all herbs are drugs, but any that are used as medicines share a common definition with drugs. This makes sense when you consider that, other than spices, the majority of herbal products sold are referred to as herbal medicines. You do not see them peddled in the drugstore as herbal dietary supplements. My point is simple: While the FDA looks the other way, patients are taking herbal medicines with the clear expectation that they are drugs. The big money comes from the implication that herbs can cure a disease.
One common example is Ginkgo biloba. Why is it a dietary supplement with no guarantee of the purity of its potency in the United States, but is licensed as a drug in France and Germany? In her 1997 article in the Consultant Pharmacist, Caren McHenry Martin, Pharm.D., stated, "According to Consumer Reports [12(6):631-636], sales of herbal medicines in the retail setting represent a $1.5 billion market," growing at a rate of more than 15% annually. Extrapolating from this, we can conservatively estimate consumer purchases to be currently over $2 billion. With this kind of profit motive and incentive to stretch the truth, does it not seem logical that every effort should be made to verify advertising claims, promote clinical research and scrutinize its results, and ensure safe manufacturing practices?
The case becomes even stronger when we consider key points Martin made on consumer use. She stated that patients are seeking herbal medicines to avoid the side effects of conventional medicines; patients are spending as much on non-conventional therapies as they are on hospital care. I am for consumer choice, but it is disconcerting to imagine a patient abandoning a physician-supervised drug regimen and replacing it with a questionable herbal remedy.
I am not against herbal remedies. In fact, as a graduate student I was fortunate to obtain a job as a pharmacognosy assistant. Part of my responsibilities included tending the greenhouse of medicinal plants used in research. In addition, I was able to attend scientific meetings and learn from icons in pharmacognosy, such as Norman R. Farnsworth, Ph.D.; Varro E. Tyler, Ph.D.; and E. John Staba, Ph.D. These experiences left me with a profound respect for herbal medicine, and it is this respect that makes it difficult to tolerate the hypocrisy of the current official stance. One need only reflect upon examples such as foxglove (Digitalis purpurea), Madagascar periwinkle (Catharanthus roseus) (vincristine, vinblastine) and belladonna (Atropa belladona) (atropine, hyoscyamine) to appreciate the power and potential dangers of herbal medicine.
The first edition of the Pharmacists' Letter lists over 20 herbs that are included in various proprietary products intended for weight loss or as dietary supplements. With society's motivation to lose weight, we can expect high utilization of these products. Unfortunately, many of these herbal ingredients may have pharmacologic effects that counteract the drug regimen goals for your patients. For example, products containing ginger (Zingiber officinale) can prolong bleeding times in anticoagulant therapy. Adding guarana (Paullinia cupana), kola nut (Cola acuminata) or yerba maté (Ilex paraguariensis) to weight-loss products may explain your patient's complaints of insomnia, anxiety or heart palpitations, because these herbs contain large amounts of caffeine. Kava-kava (Piper methysticum) may potentiate other central nervous system depressants. In addition, the patient may not even share with you the fact that they are taking herbal products; patients may not perceive them as important enough to mention.
One anecdotal case study illustrates the problem in the lack of standardized potency between products. I was asked to consult on an elderly nursing home resident with a diagnosis of major depression. She was doing reasonably well on fluoxetine (Prozac) 20mg/day, with target symptoms of crying episodes and withdrawn behavior mitigated and no insomnia or gastric distress. In June 1997, the television newsmagazine "20/20" referred to St. John's wort (Hypericum perforatum) as "a truly startling medical breakthrough-one that could affect millions of people that suffer from mild depression." In response to this, the nursing home resident began insisting on replacing fluoxetine with this herb. In order to comply with her wishes, we tried tapering her off fluoxetine and using only St. John's wort. On this regimen, her depression soon returned.
We re-established her stability on fluoxetine 20mg/day, but again at her insistence she began taking St. John's wort as well, and she began to show signs of serotonin syndrome. We then tried a compromise using fluoxetine 10 mg/day plus St. John's wort, and she achieved a therapeutic response similar to the fluoxetine 20 mg/day. There was more variability, however, in control of the patient's depression symptoms and alternating serotonin side effects. She ultimately gave her permission to return to conventional therapy. St. John's wort's therapeutic benefit was variable and unpredictable, which we subscribed to different amounts of active ingredients from batch to batch, maybe even from tablet to tablet. This previously stabilized resident had to endure several unsuccessful drug regimen changes in response to the pressures of direct-to-consumer advertising, coupled with an ineffective FDA stance on herbal products.
Returning to our pledge of primum no nocere, literature articles are beginning to suggest that it would be prudent to regulate herbs as drugs. For example, in the August issue of Psychiatry Drug Alerts (14[8]:61), there is a case study of an 80-year-old woman with Alzheimer's disease who experienced a coma the authors believe was secondary to combining Ginkgo biloba with trazodone (Desyrel).
Further, in Child and Adolescent Psychopharmacology News, Tannis M. Jurgens, Ph.D., noted that ginseng (Panax ginseng), echinacea (purple coneflower), Ma-Huang (Ephedra sinica) and juniper (Juniperus communis) have caused adverse psychiatric symptoms and should be avoided in predisposed patients. The author concluded, "Herbal medicines must demonstrate efficacy in the same rigorous clinical trials as other pharmaceutical agents and must have quality and safety issues resolved before they can be considered as first line treatments."
It is obvious that herbal medicines are being used as drugs by the general public. It is also obvious that respected clinicians acknowledge the importance of side effects and drug interactions of some of these herbal products with traditional therapies. While the National Institute of Mental Health has called for tightly controlled studies of herbs versus antidepressants, the FDA continues to avoid a mandate to review herbal products for efficacy or safety. The direct-to-consumer marketing machine accelerates, and unregulated claims of miracle cures continue to mislead consumers.
The most powerful alternative to FDA intervention is for the clinician to take the time to educate patients on the power and potential pitfalls of herbal medicine. Are we doing this? Not very well, the literature suggests. In a recent study by Chang et al. (Ann Pharmacother 2000;34[6]:710-715), pharmacists were given a 15-item herbal medicine knowledge test. Almost half the pharmacists had previous continuing education on herbal medications, and almost three-fourths of them actually sold herbal medications in their practice settings. The test results yielded an average score of only 6.3 correct answers out of 15. For those of you who don't want the FDA to step in, we are going to have to give the patient correct information more than 42% of the time.
One parting thought: On March 13 of this year, gammahydroxybutyrate (GHB) was listed in Schedule I of the Controlled Substances Act. In the late 1980s, GHB was sold in health food stores as a dietary supplement for weight loss and to induce sleep. After over 65 documented GHB-related deaths, and countless date-rape assaults, it is no longer a supplement. It is a drug. Did we really need to wait over 10 years to figure that out?
Dr. Snodgrass is an independent consultant and president of Triad Management Group. His firm assists health care managers in pharmacy systems analysis, vender evaluation, medication utilization and quality assurance in long-term care, residential care and psychiatric facilities.