© Geriatric Times. All rights reserved.
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.