HERBAL
MEDICINE
(Investigator
171, 2016 November)
History
In
the absence of information or empirical evidence, the beneficial or
deleterious effects of herb ingestion could only be discovered by trial
and error and by observing the effects on birds and animals. One can
only speculate on what the cost in human terms must have been before it
could be determined what was and what was not safe to eat.
A
considerable mythology has arisen around herbs, in particular, the
doctrine of signatures — the principle that the external
characteristics (such as shape) of a plant, animal, or other entity
signal its magical or healing properties and that relationships exist
between the appearance of a source of medicine and the diseases against
which it is effective. For example, the Pulmonaria plant, with its speckled
leaves resembling the lungs, was considered appropriate as a remedy for
lung disease, and a ginseng root in the crude shape of a human male was
considered to be an aphrodisiac. It was also a medieval belief that a
beneficent creator would not expose us to ills without also supplying
remedies. In reality of course, the chemicals in plants have evolved as
a defence against predators, not for our purposes.
With
the invention of written language, the results of experience could be
recorded and evaluated for future reference. We know from clay tablets,
written in cuneiform, that the Sumerians used licorice, mustard, opium
and thyme for medicines, and that the Egyptian Ebers Papyrus of about 1500 BC,
listed more than one hundred and twenty-five plants as well as hundreds
of prescriptions for disease and accidents. Earlier, the Chinese
recorded a materia medica, the Shen
Nung Ben Tsao, which listed more than three hundred medicines,
and a revised edition was published in 659 AD., the work of some two
thousand scholars.
In
1578, Li Shih-chen, possibly China's greatest naturalist, published his
Ben Tsao Kung Mu, or the
Chinese Pharmacopoeia. This magnum opus listed over one thousand
botanical species and a similar number of standard medical
prescriptions, many of which are in current use. India too, has its
pharmacopoeia of some two thousand plants which form the basis of
Ayurvedic medicine.
In
1640, English herbalist John Parkinson produced his massive Theatrum Botanicum — eighteen
hundred pages detailing three thousand eight hundred plants, and
shortly afterward, Nicholas Culpeper produced his classic work, The Complete Herbal. By the middle
of the nineteenth century, in Europe and in the US, almost eighty per
cent of medicines were plant derivatives.
Since
the 1980s, the health food industry and multilevel marketing companies
have aggressively marketed herbal remedies under the guise of "dietary
supplements" to evade having their products regulated as drugs.
World-wide, vitamins, herbs and supplements are a multi-billion dollar
industry with enormous power and political influence.
Theory
Why
primitive man turned to plants for medicinal purposes is a matter for
conjecture. Plant life already provided food, clothing and shelter, why
not healing properties? Perhaps it was simply a "medical instinct” — a
subconscious awareness that nature has provided.
Practice
Plant-based
products have been and still are used for a great variety of medicines
and preventatives. They take the form of liquids, powders, pastes,
balms, aromas, liniments, tinctures, poultices and ointments to be
eaten, swallowed, inhaled or applied.
Assessment
Although
herbal medicine has been around for thousands of years, longevity is
not necessarily a criterion with which to measure its efficacy.
It
is no secret that health hazards from using herbal remedies can range
from acute toxicity to insidious, long term effects. In recent years,
medical and scientific literature has frequently drawn attention to
actual and potential liver damage as a result of using herbs. Two
well-known remedies, comfrey and sassafras, fall into this category.
However, potential harm attends the use of many other herbal therapies
if they are not used appropriately.
Is
there sufficient information and adequate controls available to protect
individuals? The answer is no. More quality is needed, whether it is
provided by practitioners or governments.
A
significant percentage of drugs trace their origin to plants. However,
very few (almost none) are used in their raw form as drugs. When a
plant shows potency, drug companies try to identify and improve on its
structure.
There
have been many botanical remedies that have worked consistently and
effectively to treat many ailments, and many substances derived from
plants form the basis of commercial medications for the treatment of
such complaints as heart disease, high blood pressure, pain and other
problems. Ephredine, an active ingredient in the herb ephreda used by
the Chinese for over two thousand years, is currently used in
pharmaceutical preparations for the relief of asthma. Digitalis, the
powdered leaf of the foxglove plant discovered in 1775, is used as a
cardiac stimulant.
There
are numerous books on herbalism available, many of them the self-help
variety. Although nearly everybody does a certain amount of
self-diagnosis and medication, caution is advisable as many herbs are
potent substances. It should be noted that herbology and herbalism are terms with no
scientific or legal meaning that refer to "the study of herbs".
Any
substance capable of exerting a medicinal effect is also capable of
producing adverse side-effects. Some of the problems associated with
herbal product manufacturing and marketing include:
1.
Inadequate information on labels to enable health professionals to make
clinical judgments when patients experience problems.
2.
Failure to properly identify plant sources used in the product.
3.
Failure to standardise dosages and to identify and track batches during
production.
There
have been an increasing number of reports of harm ensuing from herbal
preparations. Serious injuries and deaths have been associated with the
use of pennyroyal, ephedra and caffeine combinations, ermanda,
chaparral, lobelia, willow bark, stepania, magnolia, yohimbe, comfrey,
licorice root and diuretic herbs to mention a few.
Although
the public's general perception of herbs is that they are nature's gift
to man and being "natural" can do no harm, many of them are highly
toxic. Some natural substances can cause cancer and induce tumours. For
example, the breast cancer drug, taxol is derived from the bark of the
pacific yew tree. The toxicity of the Taxus species is such that in
1993, there were nine hundred and sixty-nine cases in the US alone of
human poisonings attributed to yew. Any attempt to categorise herbs as
"alternative" "complimentary" or "holistic" would be treading on thin
ice. They could well be all three. Consider the following.
Until
recently medical doctors have not considered herbal medicine a subject
of discussion. Today, most are indifferent, puzzled, or curious. It has
been implied that the reason for this is because herbal medicine is
taking customers away from the multi-million dollar prescription drug
industry which underwrites the very existence of medical associations.
This of course, may or may not have an element of truth in it, and
although it has been hotly debated, begs the question whether or not
the prescribing of herbal preparations should be incorporated into
mainstream medicine. However, the same accusation could be levelled at
the herbal companies who supply herbal preparations to herbalists, as
it too is a multi-billion dollar business. Any hostility by the medical
profession is more likely to be the lack of substantiation of the
claims made on behalf of herbal medicine. It would appear then that the
question has, to a certain extent, already been answered.
To
go into any great detail about the pros and cons of herbal medicines
would require a book in itself. For the purpose of this assessment
therefore, I will confine my comments to one of the more popular
products — herbal teas.
A
plant produces a wide variety of chemical compounds that can affect the
human body — acids, tannins, essential oils, alkaloids and glycosides.
Since some alkaloids and glycosides build up in body tissue, it's
possible for them to build up to significant levels. From time to time,
new evidence of toxicity comes to light causing some long-accepted
herbal products to be dropped from the list of those generally accepted
as safe products. In recent times, substances derived from the plants
calamus, sassafras and the tonka bean were considered safe. Subsequent
research determined that they were either toxic or carcinogenic.
People
drinking herbal teas expose themselves to thousands of chemicals about
which little is known and that have not been subjected to research to
determine their safety. Some companies have gone overboard with claims.
For example, during the 1980s, Herbalife International received adverse
publicity for making illegal claims that various herbal ingredients
were effective against more than seventy diseases and conditions. In
1986, Herbalife agreed to pay U5$850,000 and to abide by a long list of
court ordered restrictions on claims and marketing practices.
One
ingredient in Herbalife's Thermojetics system at that time was the herb
ma huang. This herb contains ephedrine, a decongestant that poses risks
for individuals with high blood pressure, glaucoma and several other
conditions. Canada banned the sale of products containing ephedrine in
1994, and Texas followed suit following reports of several deaths and
serious illness among abusers of products containing ephedrine.
Fourteen
commercially available herbal teas, including the popular chamomile
tea, listed in American Pharmacy,
Vol. NS28, No.4, April 1988/231, contained toxins that could result in
adverse conditions such as severe watery diarrhoea, hepatic failure,
hallucinations and hepatocarcinogen. Comfrey tea has been linked to
liver disease, and lobelia tea can cause vomiting, breathing problems
and convulsions.
As
a guide for using herbal remedies, it is suggested that the following
should be kept in mind.
* It should not be
assumed that because something is natural it is safe.
*
Plants are also sources of potent chemicals and can be highly toxic.
*
Children should not be given herbs.
*
Large quantities of any type of herb should not be taken.
Beware
of exaggerated claims made on behalf of herbal preparations and do not
trust your health to unqualified practitioners using titles such as,
"herbalist", "herb doctor" and "herbologist".
Advice
from heath food store employees should not be taken as qualified
medical advice as few, if any have had medical training — they are
there simply as salespersons.
Richard
Hyatt, an advocate of Chinese herbal medicine, had this to say in his
book, Healing with Chinese Herbs:
''The author wishes
to impress upon the reader that this text is by no means to be
considered a home medical adviser ... some of these herbs can be
extremely toxic when used incorrectly. In certain cases Chinese herbs
alone would not be sufficient to treat the illness and should be used
in connection with acupuncture, diet, massage, and/or Western medicine.
In such cases reliance on herbs alone could allow a disease to progress
to a more serious stage".
A
caution such as this from an advocate leads one to ask why use Chinese
herbs in the first place?
References
Am
Pharmacy. 1988. Many herb teas are toxic, NS28:230-1. April 1988.
Baron,
R.L. and Vanscoy, G.J. 1993. Natural Products and the Athlete: Facts
and Folklore. The Annals of
Pharmacotherapy, Vol. 27. pp 607-615. April 1993.
Griggs,
Barbara. 1987. Green Pharmacy,
Robert Hale Ltd., Clerkenwell Green, London.
Huxtable.
1992. The Myth of Beneficent Nature: Risks of herbal preparations, Annals Intern Medicine Vol. 117,
No.2, p.165-166. July 15, 1992.
Hyatt,
Richard. 1984. Healing with Chinese
Herbs, Healing Arts Press, Rochester, Vermont.
Larkin.
1983. Herbs are often more toxic than magical, FDA Consumer, October.
Le
Strange, Richard. 1977. A History of
Herbal Plants, Arco Publishing, New York.
Snider,
Sharon. 1991. Herbal Teas and Toxicity. FDA Consumer, p. 31-33, May 1991.
Tyler,
V. 1993. Herbs of Choice,
Harworth.
[From: Edwards, H.
1999 Alternative,
Complementary, Holistic & Spiritual Healing, Australian Skeptics
Inc]