An Introduction to Medicines from Plants
Who Uses Plant Medicines?
It is estimated by the World Health Organization that
approximately 75-80% of the world's population uses plant medicines either in
part or entirely. For many this is out of necessity, since many cannot afford
the high costs of pharmaceutical drugs. Growing numbers of American health care
consumers are turning to plant medicines for many reasons - low cost and
seeking natural alternatives with fewer side effects are commonly cited.
The medicinal herb market in San Jose, Costa Rica.
Everything from birds' nests to leaves to roots to berries is available here.
How Does a Plant Medicine Become Popularly Used?
Historic use: based upon the traditions of Europeans,
Chinese, Egyptians, American Indians, and other cultures. Information on plant
medicines handed down over the centuries. Currently anthropologists and other
scientists are investigating newly-discovered cultures (visits with shamans in
Amazonia and Belize, for example), to determine what plants are being used -
this "ethnobotany" has introduced a number of new compounds into pharmaceutical
In Peru, an old Quechua gentleman was showing us around the
ruins. I said I had "soroche muy malo" - a bad headache from the altitude. He
said "uno momento" - and found a small bush - a type of mint - the leaves of
which, when crushed and the vapors inhaled, made the pain go away immediately.
I spent the next few days wandering around Cuzco with my pockets full of
Extrapolation: thinking that some activity in vitro - in
the test tube or in the lab - implies major activity in humans.
Testimonials: a famous person announces the discovery of a
"wonder drug" herbal medicine responsible for miracle cures. Suddenly everyone
is using it.
Phytomedicinal prospecting":screening plants for
biological activity. Huge projects are currently underway by such organizations
as INBio, Costa Rica's National Institute of Biodiversity. INBio is cataloging
all species of plants and animals in the country - estimated to be around
500,000! To complete this ambitious task they train "community taxonomists" to
identify plants and animals.
James Duke, Ph.D., leading a workshop on "Pharmacy From the
Rainforest", which I had the good fortune to attend, in Costa Rica. Dr. Duke
has studied the traditional plant medicines used by multiple new world
Current Legal Status in the US: The US currently has an
"open market" for anything labeled as a "nutritional supplement". This is both
good and bad - it means "caveat emptor" - let the buyer beware! Unfortunately
the buyer may occasionally be gambling with their life if they are not making
knowledgeable choices. Since "nutritional supplements" are not sold as a
treatment for a specific problem, they buyer must be informed. The bad aspect
of this open market approach is that even products with proven health benefits
may not be marketed for that use unless the producer has gone through the FDA
protocols for determining safety and efficacy (at a cost of $500 million
dollars for a non-patentable product, no one would do that!). The best example,
perhaps, of this restriction is that it would be absolutely illegal to sell
prune juice as a treatment for constipation! While no one would argue that it
is safe and effective, no one has gone through the rigorous FDA approval
A current controversy surrounds the sale of products containing
natural sources of ephedrine. Ephedrine is an adrenaline-like compound found in
some plants, especially ephedra species such as Ma Huang and Mormon Tea. This
stimulant is found in "thermogenic" weight loss products and also sold as a
"legal amphetamine" under such names as "Herbal Ecstasy". A number of people
who have taken excessive amounts of this drug have died. The FDA is currently
mulling over the idea of taking it off the market. Manufacturers are hurrying
to change the labels and provide warnings in an effort to prevent FDA action.
Not To Be Confused With: Homeopathy: this school of
healing, although it frequently uses plant sources, is not the same as "herbal
medicine" or "phytomedicine". Homeopathy is based on a theory that products
that cause symptoms in large doses may treat those symptoms in very very small
doses. Since this frequently involves diluting the initial mixtures millions of
times, the belief is that the "essence" or "spirit" of the material stays with
the diluted mixture. To some extent there are valid examples of this - a very
large (toxic) dose of aspirin may cause a fever, for example - but this
difference is tenfold, not a million fold. Many people swear by homeopathy - it
may work. But herbal medicine involves consumption of plants in order to get
vital chemical compounds in sufficient quantity to elicit changes in the
"Doctrine of Signatures": this is a religious or spiritual system
of beliefs which holds that God put plants on the earth for their medicinal
properties and that we are clued in to their action by their shapes or other
properties - that a leaf which looks like a kidney will treat kidney problems,
etc. There are plenty of example of this if you look far enough. Although this
method undoubtedly guided many early experimenters, I personally confess to
being trained in a more scientific school of thought, and think that life is
not this simple. An interesting example, though:
Saw Palmetto (Seranoa repens):
berries from saw palmetto (the smaller plant on the right - seen here near my
office in Florida) is used to treat certain urinary problems. The early
indigenous peoples of Florida discovered this property. They no doubt tried
this because the juice of these berries looks and smells just like urine!
Current Industry Problems:Is the "natural" product you are
buying really what it says it is??? This problem has long plagued the industry.
When some dried root or leaf products sell for $80 per pound, the temptation to
add a little extra something along the way goes from the harvesters to the
middlemen to the retailers - all of whom are paid by the pound. There have been
studies of retail ginseng, for example, which show numerous purchased products
with no ginseng content whatsoever! Perhaps these products rely on the power of
suggestion! Looking at this more innocently, a peasant in the Amazon may not
know one plant from a similar-looking cousin. The industry is establishing
standards in an effort to improve its credibility - some products, such as
ginkgo, are now standardized and offer some uniformity.
Environmental damage: - "wild-harvested" plants are
frequently harvested with little regard to the environment and the long-term
viability of the species. Uña de Gato, for example, has been promoted
world-wide as a cure-all and cancer treatment based solely on testimonials of a
few. The alleged active part of the plant is the inner bark - so this plant
must be killed to harvest it. Vast areas of rainforest are now being stripped
of this plant to feed the worlds' cravings for an unproven cure. "Sharks don't
get cancer" - so now everyone is taking shark cartilage. They might rather die
from cancer in old age than be killed for their cartilage, however... Besides -
who says they don't get cancer? I never saw an armadillo with cancer, or a
duckbill platypus... There is an active ingredient in shark cartilage which may
be helpful (if taken in larger quantities than you and I can afford) - but the
same action can be obtained from certain plant preparations! See next section.
Herbal products from the Amazon rain forest are available
to treat any problem you might have in the marketplace in Iquitos, Peru.
What Might Be Useful: a Few Examples
Garlic: Garlic has been shown to reduce cholesterol about
12% and to reduce platelet adhesiveness (the reason an aspirin a day is
recommended to reduce the risk of stroke and heart attack). Huge controversy
exists over what forms (other than fresh) provide sufficient allicin (the
active ingredient) activity. Fresh garlic tends to cause heartburn and social
consequences. Garlic preparations in oil have been found to be relatively
useless in some studies. Coated tablets are probably good - the "odorless"
kind. Some experts, however, say "if it don't stink, it don't work". The
equivalent of 4 to 5 cloves per day is recommended. A 1992 German study of 18
commercial preparations showed significant allicin activity in only five.
Ginkgo: Flavone glycosides ("ginkgolides") have been shown
to reduce capillary fragility and decrease blood cell transit from inflamed
capillaries. They have been shown to reduce "PAF" - platelet activating
factor". These glycosides are also potent anti-oxidants. Ginkgo preparations
are used in Germany to treat "reduced intellectual capacity and vigilance"
associated with aging, as well as to treat peripheral vascular disease.
Available in Germany in liquid, tablet, and injectable forms, in 1988 over 5.2
million prescriptions were written - even though it is also available
over-the-counter. Germany's Commission E, established to study plant medicines,
declared ginkgo as safe and effective with very few side-effects (occasional
headache). It should be taken three times daily with meals. HYPE
ALERT: Ginkgo is being widely advertised as a product which will
improve mental functioning of anyone who takes it - this is NOT
TRUE! Studies in the elderly have shown some benefit, whereas studies
in middle-aged and younger people have not shown any significant benefit.
Feverfew :Contains parthenolide, a "sesquiterpene
lactone", which acts as a serotonin antagonist, inhibiting release of serotonin
from platelets. Quite effective at lowering the frequency and severity of
migraine headaches. It may abort early attacks. Fresh leaf is most effective,
although frequent chewing of fresh leaf may cause mouth ulcers. There is
significant variability in activity in both dried and fresh products.
The Purple Coneflower of the prairies was
used by the plains Indians as a general treatment of viral illness. It has been
found to stimulate phagocytosis (ingestion of invaders by white blood cells)
and the production of healthful compounds such as properdin and interferon. It
may stimulate production of tumor necrosis factor. It is used frequently in
Germany in the treatment of viral illness or in conjunction with antibiotics
for bacterial illness. It is also being studied as an adjunctive ("add-on")
treatment of certain cancers.
Cranberry Juice or Extract: This and related Uva
Ursi extract has been shown to inhibit the activity of "adhesin", which is
needed for the pili, or tiny hairs, on the E coli bacteria to stick to
the cells lining the urinary tract. They may therefore be useful in the
treatment and prevention of bladder infections with those bacteria.
Saw Palmetto: Extract of this Florida fruit contains
5-alpha reductase activity as well as other factors which inhibit production of
prostaglandins. This and stinging nettle extract has been approved by the
German government for the treatment of the symptoms of benign prostatic
hypertrophy. It is perhaps the most widely used treatment for this disorder in
Europe. The FDA has expressed some concern that widespread use here might delay
those with prostate symptoms from seeking evaluation which might reveal more
serious problems such as cancer. My experience with recommending saw palmetto
to patients as a natural option for treatment of their symptoms has been mixed
- it seems to have helped some, while others have had no relief until we went
with prescription chemicals.
Valerian: The roots and rhizomes of Valeriana
officianalis have been used as a sleep aid for perhaps over one thousand
years. Its' effectiveness as a minor sedative or calmative continues to be
confirmed. It is safe and effective and a good recommendation for those with
minor difficulties or in whom an addictive alternative might be risky. It is
frequently combined with hops and/or passionflower, two other safe and
effective sedating herbs. Historical note: when the Latin name of a plant has
the term officianalis in it, it means that it was grown in the monks'
garden and kept in the office for medicinal uses.
Others of Interest: Hawthorne - has shown some beneficial
effects on the heart in heart failure. Melissa officianalis - lemon balm
- has been shown to have some anti-herpes effects. St. John's Wort has been
shown to have some anti-depressant activity. A chemical constituent,
hesperidin, is being studied for possibly anti-retroviral (HIV) activity. This
plant may cause photo-toxic reactions. Milk thistle is used frequently in
Germany to protect the liver from toxins such as poison mushrooms. It may be
effective for other toxins such as alcohol.
The mammosa, commonly called the "titfruit" in Costa
Rica. A member of the solanum, or eggplant family, it is used to treat sinus
infections in a number of creative ways. Eggplant extract is used to treat
various skin cancers in several countries.
A Good Source of Information: The American Botanical
Council is an objective organization which studies the uses of plant
medicines. They are based in Austin, Texas, and publish a quarterly journal,
HerbalGram. This journal contains no product advertising and endorses no
specific products. Several books by Varro Tyler, a highly-respected
phytomedicinal researcher, are excellent - they are; The Honest Herbal,
and Herbs of Choice. These books are available through the American
Botanical Councils' bookstore. The American Botanical Council is located at
P.O. Box 201660, Austin, TX 78720. Their phone is: 512-331-8868, their fax is:
512-331-1924. Subscriptions are $25/yr, $45/2 years, or $60/3 yrs. They also
organize yearly conferences on "Pharmacy From the Rainforest" - in Belize, in
Costa Rica, and in the Amazon. These conferences are excellent for anyone
interested in this subject. For further information see the
Council's web site!
© 1999 Dr. Stephen Blythe