Also see, "How
to Determine If You Can Take Herbs with Your Drugs."
Negative drug-herb interactions (side effects as the result
of taking drugs and herbs at the same time) have been over-hyped
because of fear, lack of knowledge and sheer speculation.
Although there are some negative interactions, research
has also discovered positive interactions between
drugs and herbal formulas.
Drug-drug interactions are a much more serious problem
than either herb-drug or herb-herb interactions. This is
because drugs are high doses of single, active, unstable
chemicals, while herbs contain multiple ingredients, some
of which are natural buffers.
Chinese herbal formulas are even more broad, comprehensive,
and balanced than single western herbs. (When I talk about
western herbs, I mean many of the single herbs you can buy
in stores which are part of the western herbal tradition...
and were not part of the chinese herbal tradition.)
Which is Safer - Single Herbs or Herb Formulas?
Herbal formulas are safer. The more singular a substance
is, the more likely it is to cause side effects and interact with
other substances. Studies bear this out- a number of them indicate
that drugs negatively interact more with single herbs than they
do with herbal formulas.
From most dangerous to safest (in order) are these
|Type of Combination
Situation and Results
|1. Multiple drugs
||The result of one or more physicians prescribing
you one or more drug; interaction range from discomfort to
|2. Drugs + single western herbs
||1 or more physician-prescribed drugs + you buy
yourself 1 or more single herbs
|3. One drug alone
||Can still have mild to strong side effects
|4. One herb alone
|Mild side effects are possible
|5. Multiple single wester herbs
|You buy several herbs for yourself and they
may interact, especially if the combination is not based on
tradition or research
|6. Drug + herb formula
|Prescribed by both a western and chinese-style
physicians; based on research and guesswork. The results of
such studies have been positive. The appropriate formula is
often able to balance out the drug's side effects and/or boost
7. Single western herb + chinese herb formula
|Again based partly on tradition and partly guesswork.
Some unexpected interactions are possible but should be mild.
|8. Personalized chinese herbal formula alone
||Based on diagnosis, tradition, and research.
There should be little or no unexpected interactions or side
effects, and if there are, the physician can modify the formula
to better suit you.
Our current habit of purchasing single herbs like ginseng
and gingko (amateur self-prescription) is more dangerous
than seeing an acupuncturist for a personalized chinese herbal
formula. Did you know that at least 6 million people in the U.S.
take ginseng singly? (Read
more on ginseng) Also read number 10 in the next section...
In addition, when you take several drugs and several single herbs,
there are many more potential interactions... that real-world
situation is more complex than any of our research has investigated.
So, it's a good rule of thumb to take as few drugs and single
herbs as possible.
The safest therapy options are just about the reverse
order of the list above... in order from most to least safe:
- Personalized Chinese Herbal Formula
- Single western herb + chinese herb formula
- Drug + herb formula (this is probably more effective than
#2, but possibly more dangerous)
- Multiple single western herbs
- One herb alone
- One drug alone
- Drugs + single western herbs
- Multiple drugs
These are not hard and fast rules. In some situations, multiple
drug therapy is the best choice... I urge you to review your
options with your western and chinese-style physicians, and
together you can all make the best decision.
Negative Drug Herb Interactions
1. Pain Medications
Sometimes herbs and acupuncture can neutralize the effect of
pain drugs. For example, patients on neurontin or morphine
need to be treated differently. Acupuncture in these patients
should be of shorter duration with less stimulation and subtler
point selections (like eight extra points, e.g.). Moxibustion
is a helpful alternative.
2. Chinese Licorice
Gan cao (chinese licorice) is sometimes problematic
it is in many herb formulas, but in low dosages. Higher dosages
can lead to fluid retention. Gan cao can also reduce the absorption
of oral tetracycline and some other meds, and can offset the pharmacological
effect of spironolactone. The rule of separating the dosage times
of herbs and drugs solves this problem.
Tannins are insoluble with antibiotics. A few herbs such as Da
Huang (rhubarb), He Zi, and Mo Yao (Myrrh) contain tannins. Tannic
acids may inhibit the absorption of iron.
Glycosides, which are active ingredients in many herbs, are neutralized
by acidic drugs. That means that, for example, Vitamin C (ascorbic
acid) and nicotinic acid could prevent your herbs from working.
Patients on warfarin (coumadin) are most at risk for problems
from drug-herb interactions. Warfarin is given to thin the blood,
thus preventing the likelihood of clots blocking blood vessels
in the heart, lungs, or brain. Warfarin's dosage needs to be quite
exact to work, so we don't want any herbs affecting it. Herbs
and herbal formulas that contain blood movers must be avoided.
This includes, among others, herbs dan shen (salvia), dang gui
(angelica), and yan hu suo (corydalis), and herb formulas like
xue fu zhu yu tang, di dan tang, and tao he cheng qi tang. Feverfew,
garlic, Ginkgo, ginger, and ginseng may alter bleeding time, and
so they also should be avoided by patients on warfarin.
6. Dan Shen (Salvia)
Salvia (see #5) can also reduce the effectiveness of anti-ulcer
7. Surgery and Herbs
It's a good idea to stop taking herbs 5 days before surgery,
and then after surgery take herbs only to rebuild the body.
8. Drugs for the Heart
Ma Huang (ephedra) should not be taken (even in an herbal formula)
if your are on digitalis or any other heart drugs. It also
reduces the effectiveness of anti-anxiety and sedative drugs,
and increases the cardiovascular effects of caffeine.
Kyushin, gan cao (licorice), plantain, uzara root, shan zha (hawthorn),
and ren shen (ginseng) may interfere with digoxin.
9. St. John's Wort
Studies have shown that patients who take St. John's Wort
while on a Selective Serotonin Re-uptake Inhibiting (SSRI)
anti-depressant end up with varying blood levels of drugs. This
means it interferes with the effectiveness of your anti-depressant.
Because its mode of action is not understood, it should be avoided
with monoamine oxidase inhibitors and SSRI's.
It also appears to reduce blood levels of cyclosporin,
a drug taken to prevent the body's rejection of transplanted organs.
And it reduces the effectiveness of the AIDS drug indinavir.
It's not yet clear whether it interferes with the metabolism of
all drugs, or just some. It may be difficult for your medications
to work effectively if you take St. John's Wort.
Ginseng plus phenelzine sulfate may cause headache, tremulousness,
and manic episodes. Ginseng should not be used with estrogens
Valerian should not be combined with barbituates.
Kelp as a source of iodine may interfere with thyroid
Echinacea could cause liver toxicity and therefore should
not be used with other known liver toxic drugs, such as anabolic
steroids, amiodarone, methotrexate, and ketoconazole
14. Nonsteroidal anti-inflammatory drugs may negate the usefulness
of feverfew in the treatment of migraine headaches
15. Kava when used with alprazolam has resulted in coma
16. Evening primrose oil and borage should not
be used with anticonvulsants because they may lower the seizure
17. Both Rhubard and Aloe cause loss of potassium through
the stool... this may increase the side effects of cardiac
glycosides and antiarrhythmic drugs.
18. Astragalus (huang qi) may oppose immunosupressive drugs,
because it tends to improve immune function.
Some of these herbs are not chinese herbs (feverfew, gingko,
valerian, kava, echinacea, everning primrose, borage). If you
saw a Chinese herbalist, they wouldn't be an issue. Plus, chinese
herbalists prescribe more balanced formulas, not single herbs,
so potential interactions with the single herbs are reduced.
Positive Drug Herb Interactions
- Gan cao increases the effectiveness of prednisone.
This benefit can be used to reduce the dosage of prednisone
in patients who have to take it long term. This reduces the
serious long-term side effects (bone density loss, adrenal insufficiency,
- In typhoid fever, research showed that those given
an herbal formula (xue yang mei) plus a sulfa drug did better
than those just given the sulfa drug. Both groups had a 100%
cure rate, but the combination group experienced few or no
- In mastitis, those given a heat and toxin clearing
herbal formula (jin yin hua, pu gong ying, yu jin, chi shao,
dan shen, qing pi) plus penicillin/streptomycin injections did
much better than those only given the injection.
- In adult primary nephrotic syndrome, one group was
simply given corticosteroids, while another group was also given
an herb formulas (dan shen, di gu pi, gui ban, han lian cao,
hong hua, nu zhen zi, gou qi zi, sheng di, zhi mu). The steroid
only group had a recovery rate of 56%, while the combined group's
recovery rate was 85%. In another study with nephritic
patients, patients given predisone, zhi mu (anemarrhena), shu
di huang (rehmannia), and gan cao (licorice) experienced less
of the corticosteroid side effects.
- Late-stage gastric cancer patients were studied. All
patients were given a drug chemotherapy combo of either methotrexate,
fluoroacil and vinblastine, or methotrexate, MFC, and fluorocil.
One of the two groups was also given herbs (huang qi,
tai zhi shen, caulis banthalobi, ji xue tang, bai zhu, fu ling,
niu zhen zi, gou qi zi, tu su zi). Side effects were cut
in half or eliminated in the chemo plus herbs group. Here's
a table of the percentage of patients who experienced specific
Chemo & Herbal Formula
|Loss of Appetite
|Nausea and vomiting
|Numbness in Limbs
Solving the Multi-Drug Problem with Herbs
Many patients are on multiple drugs. We have had success reducing
these medications over time with the assistance of herbal formulas.
An appropriate herbal formula is begun weeks or months ahead of
time. This gives the patient a 'cushion,' so to speak. Then the
drug dosage is slowly reduced. The herbal prescription is modified
as the patient progresses. MD's often cooperate with us
in this effort since they know as well as anyone the dangers of
poly-pharmacy (taking multiple drugs at once)
in the elderly. They say a good geriatric doctor stops more medications
than he starts.
Herbs are more likely to correct an imbalance permanently
(we call that "healing"). Drugs' therapeutic effects
are almost always temporary. It takes more time to do this with
but it's worth it.
Other Situations that are Helped by Herbal Formulas:
Instead of just stopping cold (or hot, as the case may be), an
herbal formula such as zhi bai di huang wan may be given weeks
or months ahead of time. Then the patient's system is more balanced
when the HRT is stopped, and rebound symptoms are less likely
and less severe.
Breaking the Antibiotic Cycle
Some patients perpetually take round after round of antibiotics.
Approaches based on the Shang Han Lun (Cold Damage Classic) such
as use of the herb formula Xiao Chai Hu Tang (Minor Bupleurum)
have been known to get the patient well and away from the constant
need for antibiotics.
Complementing Diuretic Therapy
While Chinese Herbs should never be used to add to the diuretic
effect of concurrent drug therapy, they can boost the system.
Diuretic drugs reduce the excess fluids, but they do not solve
the underlying deficiency. Herbal formulas can be prescribed to
strengthen the Spleen and Kidney systems.
Quitting SSRI Anti-Depressants
Of course this can be dangerous, and should be done with a psychiatrist
and an herbalist. Herbs such as St. John's Wort (SJW) could be
used as a cushion while quitting. SJW does not replace SSRI's
studies show that it must have some other mode of action. Herbal
formulas are better anyway. See a Chinese Herbalist.
As we saw in positive interaction #4 above, herbal formulas can
be used in conjunction with corticosteroid treatment (for conditions
like lupus, rheumatoid arthritis, primary nephrotic syndrome,
etc.). A chinese herbal formula, Bupleurum and Hoelen Combination
(Chai Ling Tang) can be used for withdrawal from corticosteroid
therapy. Subsequently, it can be used in place of the steroids
for continued treatment.
General Rules for Taking Herbs, Vitamins and
- Take them at different times. Most drugs are taken
with meals to limit Stomach irritation. Take herbs between meals
(at least 1 hour before and after a meal
2-3 hours would
be best) for optimal digestion.
- Don't take ascorbic (vitamin C) or salicylic acid (aspirin)
at the same time as herbs. The acids will neutralize many
of the saponins. Vit C will alter and neutralize herbs
so don't drink any orange or citrus juices with herbs either.
- Don't take herbs that are supposed to do the same thing
as a drug you're on. For example, don't take blood movers
like dan shen or dang gui with warfarin. Don't take diuretics
like fu ling with diuretic drugs.
- You can take an herbal formula to complement the drugs
you have to take. This can reduce or eliminate side effects.
It really requires a professional
see a Chinese Medicine
practitioner. This works well in chemotherapy to protect the
body. However, in Hepatitis C, the interferon/ribavirin treatment
requires some of the uncomfortable symptoms of fever and feeling
ill to work. Stopping those side effects with herbs has been
known to inhibit the drugs' effects. In the case of Hep C, you
can opt for Chinese Herbal therapies instead of the western
- (I must first acknowledge a great debt to Z'ev Rosenberg,
LAc who is Chair of the Herbal Department at the Pacific
College of Oriental Medicine. Many of these ideas come from
his lectures there.)
- Kelvin Chan, Lily Cheung. Interactions Between Chinese
Herbal Medicinal Products and Orthodox Drugs. Dunitz Martin
Ltd. 2000. (Most of the positive drug-herb studies mentioned
above were summarized in this source. At least one of them came
from the Beijing Journal of Traditional Chinese Medicine.)
- Miller LG. Herbal medicinals: selected clinical considerations
focusing on known or potential drug-herb interactions. Arch
Intern Med. 1998 Nov 9;158(20):2200-11. Review.
- Dharmananda, S. The Interactions of Herbs and Drugs.
June, 2001. Institute for Traditional Medicine. http://www.itmonline.org.