By Lori Solomon, Medical Tribune News Service
Americans spent $90 million on ginkgo biloba to prevent or treat
dementia, $48 million on St. John's wort to alleviate depression
and $86 million on ginseng to increase energy levels in 1997 and
the list does not stop there.
Consumers are continuing to spend more and more money on herbs
and dietary supplements to treat chronic conditions. A study in the
September/October issue of Psychosomatic
Medicine, reported that psychiatric
disorders are the most common conditions treated with complementary
or alternative medicine therapies.
Herbs and dietary supplements appear to offer benefits for those
with depression, anxiety, insomnia and memory problems. However,
the new study shows that potential side effects exist, especially
when patients mix prescription drugs with alternative therapies
often without their doctors' knowledge.
``For psychiatric disorders, particularly depression, nobody
should self-medicate - not even physicians,'' said Jerry Cott, a
psychopharmacologist at the National Institute of Health, Bethesda,
Md., and co-author of the study. ``The lesson learned for
physicians is not to dismiss this information out of hand. Doctors
must become more informed than their patients. They need to work
with their patients.''
The researchers conducted a literature review for clinical
trials as well as for adverse effects and interactions reported for
herbs and dietery supplements used with great frequency as well as
lesser known ones. The more popular supplements investigated
include St. John's wort for depression, ginkgo biloba to improve
memory problems and dementia and ginseng for low energy. Some of
the lesser known supplements included in the study because they
offer potential benefits as a psychotherapeutic agents were
passionflower for anxiety and skullcap for nervous conditions. The
authors also reviewed studies on vitamins, amino acids and fish
oils and their use for depression.
While medical literature does indicate that herbs and dietary
supplements seem to have some beneficial effects on depression,
anxiety, insomnia and memory problems, experts caution that they
are not risk free.
``There is no real standardization,'' said Christopher Gardner,
a research associate at the Stanford Center for Research in Disease
Prevention, Stanford, Calif.
``Unlike pharmaceuticals, dietary supplements vary crop to crop,
year to year. There seem to be some benefits and there seem to be
some side effects. It is an exciting area, but we need to know
more.''
The authors of the study found the reporting of adverse effects
of dietary supplements is often problematic.
``The finding most surprising has to do with the way side
effects or adverse effects are reported -with very little
investigation,'' said Cott. ``Physicians are too ready to believe
negative information without investigation.
Cott explained that in case reports of adverse effects there is
often a failure to differentiate between intrinsic toxicity,
misidentification, contamination or adulteration as well as failure
to consider concurrent prescribed drugs or supplements as
contributors to the adverse effect.
While herbs and other dietary supplements have been used for
thousands of years, formal research demonstrating their
effectiveness as well as chemical mechanisms is a relatively new
endeavor. Cott said that larger clinical trials are needed. The
National Institutes of Health will be conducting three new trials including a study of the effects of
gingko in preventing Alzheimer's disease among the elderly, a study
of omega-3 fatty acids and bipolar disorder and a trial of kava and
its effects on anxiety disorder.
