Kenneth R. Pelletier, clinical
professor of medicine at Stanford University’s School of Medicine and director
of Stanford’s Complementary and Alternative Medicine Program, explains why many
herbal medicines hold promise but also why they should be taken with caution.
Pelletier details problems in the labeling of herbal medicines, inadequate
regulation of the industry, lack of scientific studies on safety and
effectiveness, and possible harmful interactions with other medicines.
Guide to Herbal Medicine
By Kenneth R. Pelletier
 |
| Kenneth R. Pelletier Photo Source The Healing Mind |
Herbal remedies have been used for
thousands of years. Today an estimated one-third of adult Americans—some 60
million people—use herbal medicines each year, spending more than $3.2 billion
on them. In the rest of the world, approximately 64 percent of the population
relies on herbal medicines. Despite their overwhelming popularity and long
history, we know relatively little about the safety and effectiveness of herbal
remedies. Scientific study should make these remedies far safer and more
effective in the future. Global recognition of nature’s green pharmacy should
inspire individuals and nations to protect this extraordinary resource.
As with any medical decision, it’s
important to be well informed before you use herbal medicines. Here are some
things to consider before choosing an herbal remedy:
What is herbal medicine?
In herbal medicine, the word herb
applies to any plant or plant part used for its medicinal, flavoring, or
fragrant properties. Leaves, flowers, stems, roots, seeds, fruit, and bark can
all be constituents of herbal medicines. Europeans sometimes use the term phytomedicine,
from phyto (Greek for “plant”), to describe herbal or botanical
medicine.
Before the 20th century
Early in human history, people
practiced herbal medicine as a magical or religious healing art. From these
origins, systems of herbology developed.
Botanical medicine in the Americas
evolved through the blending of two separate traditions. Passengers on the Mayflower
carried with them a book on European herbology. In America, the colonists
encountered not only new plants but also Native Americans familiar with the
properties of these plants. During the 1800s many of the most effective
American healers combined European and Native American herbalism. By the 1850s
Chinese immigrants had added their own herbal tradition to the mix, especially
on the West Coast. Herbology began to lose influence in the United States after
the Civil War, partly because conventional medicine improved during the war.
During the 20th century
By the beginning of the 20th century
chemists had become more adept at isolating the active ingredients in plants,
and the use of raw, whole-plant materials began to seem crude and unscientific.
In 1910 the Carnegie Foundation, at the request of the American Medical
Association, issued a study of American medicine called the Flexner Report.
This report elevated pharmaceutical medicine and was critical of schools that
taught herbal medicine and other nonconventional approaches. This influential
report contributed greatly to the decline of alternative medicine, including
herbology.
The situation today
Modern pharmaceuticals cannot treat
every condition effectively, and some drugs have unwanted side effects. In the
late 20th century herbal medicine made a comeback as people began to seek
alternatives to these drugs. Today more than 1,500 herbal preparations are
marketed in the United States, not only in health food stores but also in
pharmacies, supermarkets, department stores, and even truck stops.
Another indication of the importance
of herbals: About one-quarter of all U.S. prescription drugs are derived from
herbs. The pharmaceutical industry uses around 120 different compounds derived
from plants in the drugs it manufactures, and it discovered nearly
three-quarters of these compounds by studying folk remedies. Examples of drugs
from plants include quinine, from the bark of the South American cinchona tree,
used to treat some strains of malaria; digitalis, a widely prescribed heart
medication, derived from the foxglove plant; salicylic acid, the source of
aspirin, from willow bark; and taxol, for treating ovarian cancer, from the yew
tree.
Why so many precautions?
Plants can be toxic, but that’s not
the only reason consumers should exercise caution when selecting herbal
remedies.
Inadequate regulation
The herb industry is essentially
unregulated. There is no formal practice of botanical medicine, and the vast
majority of medical and pharmacy schools do not teach herbal medicine. This
lack of regulation and organized practice leaves consumers essentially on their
own in determining how to use herbal products. Some herbs have potentially
harmful side effects, so it’s important to understand the full range of their
biological activity and to talk to a physician.
Quality control and inaccurate
labeling
A test published in the September 2,
1998, issue of the Los Angeles Times examined ten common over-the-counter
(OTC) products labeled as St. John's wort. Out of the ten products, seven
contained between 75 percent and 135 percent of the amount of hypericin (the
probable active ingredient) that the label stated, and three contained no more
than half the amount stated. An unpublished study of ginseng reported similar
wide variations in the contents. As long as the herb industry remains
unregulated, manufacturers have no reason to establish quality controls
insuring that each batch of medicine contains the same amount of active
ingredient. And without quality control, many herbs and supplements will carry
inadequate or inaccurate labeling.
No safety studies
It’s important to emphasize that
there have been no long-term studies of the safety or effectiveness of herbal
preparations. (In fact, there are too few such studies on conventional
pharmaceuticals.)
All herbal dosages and
recommendations are based on studies with adults, and the safety and efficacy
of these products for children is completely unknown. Adults over age 65 may
have diminished liver or kidney function and need to be particularly concerned
about excess dosages and the toxic effects of herbal remedies or supplements. A
physician should monitor liver function periodically for older adults taking herbals.
Potential interactions
How herbal preparations interact
with foods is another unknown. Grapefruit, for example, increases the potency
of many conventional medications, such as calcium channel blockers taken for
high blood pressure, angina or chest pain, and arrhythmias, and
benzodiazepines, commonly prescribed for anxiety and sleeplessness. Grapefruit
also increases the potency of Seldane, an allergy medication that was withdrawn
from the market after the discovery of its potentially dangerous interaction
with certain antibiotics. It would be prudent to avoid eating grapefruit while
using herbs for any of these conditions.
How to use herbal medicines safely
To ensure that your are using
botanical medicines safely and effectively, observe the following precautions:
* Don’t use herbal preparations to self-treat serious medical conditions or persistent symptoms.
* Don’t give children herbal
remedies without medical supervision.
* Don’t take herbal medicines if you
are pregnant or a nursing mother.
* Tell your doctor about any herbal
remedies you are taking, because herbs can interact with conventional drugs.
* Never take more than the
recommended dosage of an herbal preparation. Stop taking the herbal immediately
if you notice an adverse reaction, and report any negative reactions to the FDA
Med-Watch line at (800) 332-1088.
* Purchase herbal preparations from
reliable, trustworthy sources.
* When taking laboratory or drug
tests, advise the person administering the test of any herbal preparations you
are taking. These herbs can trigger false findings in tests for drug abuse and
can invalidate routine lab tests.
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Source: Microsoft ® Encarta ® 2009.
Link
Site of the Author : http://www.drpelletier.com/