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Supplements and Surgery -- What to Tell Your Doctors
21 September 2001
by Wyn Snow, Managing Editor SupplementQuality.com
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 drugsd uring 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.
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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 anti-clotting medications |
Goldenseal |
|
high blood pressure; swelling |
Kava |
increase anesthesia effects |
increase anti-seizure medications and/or
anesthesia effects |
Licorice |
|
high blood pressure; swelling; electrolyte
imbalances |
Saw Palmetto |
|
interact with hormone therapies |
St. John's Wort |
increase metabolism of drugs used before and
after operations |
prolong anesthesia effects |
Valerian |
increase anesthesia effects |
increase anti-seizure medication effects or
prolong anessthesia effects |
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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.
(c) Copyright 1999-2001 Dietary Supplement Quality Initiative.
For permission to reprint, please contact the editor. SupplementQuality.coms |
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