Supplements
and Surgery -- What to Tell Your Doctors
21
September
2001
by
Wyn Snow, Managing Editor
Anyone
facing surgery wonders, "What if something goes wrong?" Patients
know to tell their doctors what medications they take; also, doctors
and nurses routinely ask for information about prescription and
over-the-counter drugs during the preparatory stages before surgery.
But what about botanicals and other kinds of dietary supplements?
Can they affect surgery and anesthesia?
The
short answer is yes, some can.
A
recent article in the Journal of the American Medical Association
(JAMA) listed eight herbs that might affect surgery or anesthesia
and recommended that doctors ask their patients what supplements
they are taking. Similarly, the American Society of Anesthesiologists
(ASA) has published a pamphlet listing common uses and potential
side effects of thirteen herbs.
SupplementQuality.com
investigated further to learn not only which supplements can affect
surgery and anesthesia -- but why and how.
Other
supplements and surgery
A
few non-herbal supplements -- such as vitamins, minerals, and other
special purpose supplements -- also have the potential of affecting
surgery and anesthesia. SupplementQuality.com asked Paul Thomas,
registered dietitian (RD) and editor/publisher of The Dietary
Supplement newsletter, which non-botanical supplements people
should be careful about before surgery.
According
to Thomas, "Vitamin E is a blood thinner, but nothing else immediately
comes to mind. It's possible one should stop taking antioxidants
during chemotherapy or radiation treatment for cancer -- but as
to how soon afterwards one can resume, or whether one should take
antioxidants afterwards to protect healthy cells, unfortunately
none of these questions have answers. There are differences of opinion,
but these are based on guesswork and speculation and little else."
Two
books that begin to address the question of surgery risks and potential
interactions between supplements and drugs are: Physician's Desk
Reference for Nutritional Supplements, and Allison Sarubin's
The Health Professional's Guide to Popular Dietary Supplements.
Which
herbs are especially important?
The
following list shows the specific herbs and potential side effects
named in the JAMA article and ASA pamphlet.
None
of these possible side effects have been proven scientifically beyond
a shadow of a doubt -- what the federal Food and Drug Administration
(FDA) would call significant scientific agreement. Both the JAMA
article and ASA pamphlet used phrases like may cause, may interact
with, may prolong throughout. However, some degree of suggestive
evidence does exist linking these herbs and potential side effects.
Herb |
JAMA
article: potential side effect risks |
ASA
pamphlet: potential side effect risks |
Echinacea |
immune
suppression (could interfere with wound healing) |
liver
inflammation in combination with certain drugs |
Ephedra
(ma huang) |
heartbeat
irregularities |
blood
pressure and/or heart rate |
Feverfew |
|
bleeding |
Garlic |
bleeding |
bleeding |
Ginger |
|
bleeding |
Ginkgo
biloba |
bleeding |
bleeding |
Ginseng |
bleeding;
low blood sugar |
blood
pressure and/or heart rate; interaction with anticlotting medications
|
Goldenseal |
|
high
blood pressure; swelling |
Kava |
increase
anesthesia effects |
increase
antiseizure medication and/or anesthesia effects |
Licorice |
|
high
blood pressure; swelling; electrolyte imbalances |
Saw
palmetto |
|
interact
with other hormone therapies |
St.
John's wort |
increase
metabolism of drugs used before and after operations |
prolong
anesthesia effects |
Valerian |
increase
anesthesia effects |
increase
antiseizure medication effects or prolong anesthesia effects |
Do
herbalists agree?
SupplementQuality.com
contacted several leading herbalists and asked them if this list
and description of potential side effects is accurate.
Roy
Upton, Executive Director of the American Herbal Pharmacopeia, agrees
that the list is basically correct -- with two exceptions. Upton
says, "I believe the warning about St. John's wort and anesthesia
was an anomaly. I'm not sure what the problem is with echinacea
and wound healing. Wound healing is one of its confirmed effects
due to its action as a hyaluronidase inhibitor. Also, many botanicals
affect metabolization of drugs. One of the most powerful is grapefruit
juice."
Herbalist
Jonathan Treasure spoke with us at length. He attended medical school
at Cambridge University in England before switching careers to focus
on herbalism, and although he does not have an MD degree, he has
participated in designing research studies at Harvard Medical School.
Treasure is a practicing clinical herbalist, a Member of the National
Institute of Medical Herbalists in the UK (MNIMH), and a member
of the American Herbalist Guild. He pointed out bias in the medical
community and literature as well as specific flaws in the JAMA article,
then recommended a different approach to the basic question of what
to tell your doctor.
Getting
solid advice about herbs before surgery
Treasure
says, "Physicians usually do not know enough about herbs to give
good advice about which herbs to continue taking and which to stop
before surgery. In the medical literature, there is a bias against
herbal medicines and a lack of education on the part of physicians.
In the popular media, there is sensationalism and ignorance and
push for readership. Hysterical stories about the dangers of herbs
attract more readers than plain, fact-oriented articles."
Climate
of opinion obscures the real issues
Unfortunately,
this climate of opinion in both medical literature and the popular
press tends to obscure the real issues of herbal use and potential
interactions between herbs and drugs. According to Treasure, "When
a patient is facing surgery, one group of physicians may say that
garlic is the most dangerous substance in the world -- whereas another
group of physicians cite placebo-controlled studies that say garlic
doesn't work. But you can't have it both ways: that garlic is simultaneously
powerful and dangerous as well as weak and ineffectual."
Foods
also affect drug metabolism
Treasure
points out that many foods also cause interactions with drugs. "Grapefruit
juice affects the metabolism of drugs (including the blood-thinner
Warfarin) by its effects on the liver and gut -- yet we don't hear
a hue and cry that grapefruit juice should be prescription only
or that patients should stop drinking it two weeks before surgery.
Broccoli and the cabbage family contain compounds that affect drug
metabolism, as strongly as St. John's wort in some cases, but we
don't hear a call for patients to stop eating broccoli."
Physicians
need better, accurate information
Because
increasing numbers of Americans are using herbs, physicians need
better, more accurate information both about the effects of herbs
and potential interactions with drugs. Treasure applauds JAMA and
the ASA for drawing attention to the need for physicians to learn
about herbal medicines, but adds, "Physicians need to look at the
literature in herbal pharmacology instead of reading hysterical
reports that are largely unsubstantiated when evaluated by scientific
criteria."
JAMA
report not based on solid scientific evidence
Of
the 122 references in the JAMA article, Treasure points out that
only 59 are primary literature. Concerning the others, Treasure
states, "There is an old joke in medical schools that the plural
of anecdote is clinical evidence. It has happened
that editorial musings have been quoted -- and then other people
repeat the quote -- and no one goes back to check the original source.
Or a journal publishes a letter about a potential interaction, and
then other physicians write in saying, 'Me too, I had a patient,'
and suddenly there is an entire climate of belief with no one doing
a serious literature evaluation to establish what the risks actually
are."
The
real issues for herbs and surgery
According
to Treasure, "Certain herbal remedies can interact both positively
and negatively with certain drugs. If you are contemplating a surgical
procedure, your surgical team needs to know what you are taking.
Surgical nurses have become very aware of this and now tend to ask
about both over-the-counter drugs and dietary supplements. So the
first concern is to communicate what one is taking. The second is
which herbs might be of consequence."
Herbs
likely to affect surgery and anesthesia
According
to Treasure, three basic kinds of potential effects are important
for surgery and anesthesia:
- hemostasis
(coagulation and clotting)
- sedative
effects (which can amplify anesthesia)
- metabolism
of certain drugs
(Surgeons
and anesthesiologists would probably add cardiovascular effects
to that list.)
Treasure
gave the following examples of these three kinds of effects. He
did not characterize these examples as complete.
Hemostasis
"Ginkgo
inhibits the formation of clots, and is therefore inadvisable
to take before surgery. However, a soon-to-be-published study
failed to show any increase in bleeding time, either alone or
in combination with aspirin in healthy volunteers.
"Garlic
affects coagulation and thins the blood.
"Several
Chinese herbs that come under general category of blood movers
(a Chinese term) act as anticoagulants. Two examples would be
dong quai and dan shen (red sage). These and other herbs can be
subtle parts of a formula with a different, perhaps dramatic name."
Sedative
effects
"Sedative
herbs such as valerian and kava may increase the effects of anesthetic
drugs and therefore influence the depth of anesthesia. A few experimental
studies suggest this possibility. In rats who are taking barbiturates
every night, the sleeping time increases for those also given
valerian. However, most herbalists would argue that people are
not the same as rats.
"In
any case, it's common sense not to take a sedative herb before
surgery. The risk is that people who are scared might take a calming
herb to relieve their fear -- so it makes sense to warn people
not to take them. However, sedative herbs are not likely to cause
irreversible coma or other huge problems."
Metabolism
of various drugs
"St.
John's wort has been shown to affect the absorption and metabolism
of certain important drugs, digoxin and cyclosporin in particular.
Cyclosporin is used for transplants, digoxin for arrhythmias --
and their concentration in the blood is critical to their effectiveness."
Other
herbs on the JAMA/ASA list
Echinacea:
Treasure states, "The JAMA paper says echinacea causes complications
for wound healing, which is opposite to the truth. There is no evidence
for liver inflammation."
Ephedra,
which is arguably the most controversial herb on the market today:
Treasure agrees that cardiovascular integrity is important in surgery
(blood pressure and heart rate/rhythm), then points out, "Sure
ephedra affects the heart -- but physicians don't tell their patients
to stop taking Sudafed before surgery." [Sudafed is an over-the-counter
medicine that contains pseudoephedrine, one of the two main bioactive
compounds in ephedra.] (However, see also our sidebar on ephedra
and surgery.)
Ginseng:
Treasure says, "If ginseng was a significant hypoglycemic,
it would be used instead of insulin."
Licorice:
Treasure observes, "Licorice has gotten a bad press -- mostly
from concentrates in revolting things like chewing tobacco. There
are no clinical reports of adverse effects from herbal use of licorice.
It does have side effects, but there are no reports of therapeutic
dosages of licorice root causing side effects."
Safety
record for herbs
One
of the common misconceptions among physicians is that herbs have
not been tested for safety. In fact, Treasure states, "The
main safety data for herbs comes from the fact that herbs have been
used for thousands of years. In that process, the good guys have
been picked up and the bad ones weeded out. The only problems this
doesn't catch are the subtle, silent onset type. A few herbs that
cause liver or kidney problems over a long period of time were missed.
But the vast majority of herbs have been field tested for safety."
Treasure
points out this is exactly equivalent to the kind of data the
FDA accumulates to assess risks involved with pharmaceutical drugs,
and says, "The FDA relies on community use to discover interactions.
When people start dropping dead or getting liver disease, there
is a time lag but we do discover it."
Safety
testing of pharmaceutical drugs typically involves trials of approximately
one thousand people -- but to discover a drug interaction that affects
1 in 3000 patients (which Treasure calls "a very high rate")
one needs to have a clinical trial of at least ten thousand people
taking both drugs. This is why some of the drugs that the FDA approves
are later found to be unsafe.
Treasure
says, "Even with the best will in the world, you can't catch
all the problems." He cites the case of Rezulin and says, "It
causes appalling liver disease. People were winding up on liver
transplant lists. You don't hear any hue and cry about problems
with prescription drugs -- but we do still hear about ephedra, which
it is arguable if ephedra has killed anyone even though millions
of people have taken it. But Seldane was killing people and there
was no sensational press."
Natural
not the same as safe
Treasure
also points out that natural is not the same as safe.
Traditional use has demonstrated the overall effectiveness and safety
of most herbs used today. However, some herbs are now being used
in ways quite different from traditional use. Treasure says herbalists
don't use St. John's wort as an antidepressant. Instead, "It's
a wound wort."
According
to Treasure, side effects from herbs like ginkgo and St. John's
wort are a new phenomenon caused by concentrating herbs into powders
and extracts. He says, "When they were taken as teas or tinctures,
people didn't get headaches or tummy aches. Herbs are gentle but
they do have profound effects. Today's pill consumer mentality has
in no small part created side effects that you don't see in normal
clinical practice. The more we make herbs like drugs, the more they
start having side effects."
The
trend to standardization of herbs has two aspects. One is quality
control, from growing conditions through harvesting to processing.
Another is that many "standardized" products often contain
stronger concentrations of one or more specific active ingredients
-- which makes them more like manipulated, processed pharmaceutical
drugs. So while physicians may think that's great, herbalists are
more likely to be concerned. One important foundation of herbalism
is: "The active principle is the whole plant."
A
different approach for those facing surgery
Treasure's
advice to patients: "Yes, absolutely: Tell your physician about
the herbs you are taking. Better still, also consult a practitioner
who is qualified and experienced in the use of herbs concurrently
with drugs."
According
to Treasure, most naturopaths and clinical herbalists deal with
patients who come to them taking a basketful of drugs. Patients
say, "I'm taking digoxin and a beta blocker and diuretic, and
I'm pretty much stable but I'd like to start using hawthorn. I'd
like to reduce my drug load." Rarely do patients go to a physician
and say, "I'm taking garlic and hawthorn and think I might
need digoxin, what do you think?"
Sources
American
Society of Anesthesiologists. "What You Should Know About Herbal
Use and Anesthesia." American Society of Anesthesiologists,
pamphlet, 1999.
Healthy.net.
"Herbal Medicines Can Affect Surgery." Website article,
July 2001. healthy.net/asp/templates/news.asp?Id=2678.
Natural
Products Insider website. "JAMA: Herb Use May Interfere with
Post-Op Recovery." Website article, 10 July 2001. www.naturalproductsinsider.com/hotnews/17h1016177.html.
Paul
Thomas, EdD and Registered Dietitian (RD). Personal communication,
24 July 2001.
Jonathan
Treasure, Member of the National Institute of Medical Herbalists
in the UK (MNIMH), and member of the American Herbalist Guild. Personal
communication, 24 July 2001.
Information
in the two website articles was based on a study that appeared in
the 11 July 2001 edition of the Journal of the American Medical
Association, (286:208-16, 2001). The study also appears on the JAMA
website (jama.ama-assn.org)
in an area limited to JAMA subscribers.
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