Download The increasing needs of knowledge on interaction

The increasing needs of knowledge on interaction between Chinese herbs and
drugs
Author : - Dr. Edward Tsang (registered Chinese Herbalist & Acupuncturist )
Wu Zhu Metaphysician
Use of and expenditure on herbs in Australia
A south Australian survey conducted in 2000 by Maclennan, Wilson and Taylor
found that 52% of those surveyed had used at least one non-medically prescribed
complementary and alternative medicine (CAM) (including non-prescribed vitamins,
aromatherapy oils, herbal medicines, etc.). In 2003, the maximum cost to the patient
for a patient contribution item is $23.10 for general patients and $3.70 for a
concessional patient. (3)
A 1996 report on the practice of Chinese medicine in Australia found that patients
were receiving treatment for a wide range of health conditions. Among 14 diagnostic
categories, rheumatological disorders constituted the greatest proportion of cases
being treated by Chinese medicine practitioners and medical practitioners practising
Chinese medicine (29)
Two Australian studies (30, 45) on the use of Chinese medicine found that 49% and
35% pf patients were taking herbal medicine in combination with pharmaceutical
medication.
It is important that practitioners of particular forms of CAM are adequately trained to
protect the public. For example, not all herbal medicines are safe, some can interact
with pharmaceuticals and serious adverse events can occur in practices such as
acupuncture.
Safety of herbal practices and medicines
There is limited information on adverse events associated with CAM in Australia.
There are approximately 150 – 200 reported cases of adverse reaction to
complementary medicines per year recorded by the Australian Commonwealth
Government’s Adverse Drug Reaction Advisory Committee (46). However, any
comparison between complementary medicine and western pharmaceutical medicines
in terms of risk needs to keep in mind the purpose or clinical disorders for which the
medicines are used and needs to consider an assessment of the risks and benefits of
the individual medicines. Many western medicines that have side-effects are
extremely effective in treating serious diseases and the benefits may for outweigh the
risks.
The safety of herbal practices and medicines is of concern to health practitioners and
governments. Although generally perceived as safe, many herbs are not safe and
adverse effects can include allergic reactions, toxic reactions (including renal and
hepatic toxicity), mutagenic effects, herb – drug interactions and idiosyncratic
reactions, some of which can result in death (29, 42). There are known interactions
that can occur between certain herbs and pharmaceuticals, the increasing knowledge
in this area will reduce and avoid the negative herb – drug interaction that affect
people’s health, it will also build up the confidence of public to use herbal medicine.
In fact, 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. 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 cominations (
Type of
Combination
1. Multiple drugs
):
Situation and Results
The result of one or more physicians prescribing you one or
more drug; interaction range from discomfort to lifethreatening.
2. Drugs + single 1 or more physician-prescribed drugs + you buy yourself 1 or
western herbs
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 You buy several herbs for yourself and they may interact,
western herbs
especially if the combination is not based on tradition or
research
6. Drug + herb
Prescribed by both a western and Chinese-style physicians;
formula
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 its
effectiveness
7. Single western Again based partly on tradition and partly guesswork. Some
herb + chinese herb unexpected interactions are possible but should be mild.
formula
Based on diagnosis, tradition, and research. There should be
8. Personalized
chinese herbal
little or no unexpected interactions or side effects, and if there
are, the physician can modify the formula to better suit you.
formula alone
These are not hard and fast rules. In some situations, multiple drug therapy is the best
choice. 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
Negative Results of Combining Single Herbs and Drugs
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). 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.
3. Tannins
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.
4. Glycosides
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.
5. Blood-thinners
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 can also reduce the effectiveness of anti-ulcer drugs.
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.
10. Ginseng
Ginseng plus phenelzine sulfate may cause headache, tremulousness, and manic
episodes. Ginseng should not be used with estrogens or corticosteroids.
11. Valerian
Valerian should not be combined with barbituates.
12. Kelp
Kelp as a source of iodine may interfere with thyroid replacement therapies.
13. Echinacea
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
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 threshold.
17. Rhubarb and Aloe
Both Rhubarb 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.
Selected herb-drug interactions
The information presented here is derived from a number of primary and secondary
sources, including the German Commission E monographs,5 the ESCOP
monographs,6 the WHO monographs,7 Herb Contraindications and Drug
Interactions,11 and others. Summarized here are the possible antagonistic or
synergistic interactions that these herbs may have with conventional pharmaceutical
medicines. The interactions reported in the monographs5-7 include those based on a
variety of evidence, including theoretical considerations, in vitro experiments, animal
studies, human case reports, and clinical studies. Additional information from nonmonograph sources refers to human data only (specifically case reports and clinical
studies).
?Aloe gel and juice (Aloe vera)
Aloe juice can produce an additive effect. In a clinical trial, one tablespoon (15 ml) of
aloe juice was given orally in the morning and at bedtime to 36 diabetic patients for
42 days; the result was an increase in the hypoglycemic effect of glyburide
(glibenclamide). This effect was probably due to the aloe antihyperglycemic
activity, which was demonstrated by oral administration to 36 diabetic patients, in the
same dose and for the same duration, in another study.21
?Aloe latex (Aloe vera and Aloe ferox; "drug aloe")
Long-term use or abuse of drug aloe as a stimulant laxative can increase loss of serum
potassium, thereby potentiating cardiac glycosides and antiarrhythmic agents (e.g.,
quinidine). Potassium deficiency can be increased by simultaneous use of thiazide
diuretics, corticosteroids, or licorice root.5-7 Decreased intestinal transit time may
reduce the absorption time available for orally administered drugs.7 (The aloe referred
to here is "drug aloe," made from the inner leaf latex, not aloe gel, from which
numerous drinks are made and marketed in North America. Ingestion of preparations
made from aloe gel or juice normally does not produce a significant laxative effect or
the drug interactions mentioned here.)
Similar cautions apply to all other stimulant laxatives, including buckthorn bark and
berry, cascara sagrada bark, rhubarb root, and senna leaf and fruits, which are
described below.
?Astragalus root (Astragalus membranaceus)
Astragalus root, a major herb in traditional Chinese medicine, increases the immunestimulating effects of interleukin-2 and acyclovir but may be incompatible with
immunosuppressive drugs (e.g., cyclosporine, azathioprine and methotrexate).15
?Bitter melon (Momordica charantia)
Also known as karela, the fruit of bitter melon had an additive hypoglycemic effect
when consumed as a vegetable concurrently with chlorpropamide in one case report.22
Insulin dosing in diabetic patients may need to be adjusted because of its
hypoglycemic effect:11 Dosage of 100 g of bitter melon fruit daily for three weeks
significantly reduced serum glucose in a study involving seven diabetic patients.23
Also, 0.23 kg of fried bitter melon fruit daily for 8-11 weeks before a glucose
tolerance test produced increased glucose tolerance in nine diabetic outpatients.24
?Blackcurrant leaf (Ribes nigrum)
No interactions have been reported. However, because this herb has diuretic action, it
should not be taken simultaneously with diuretics indicated for cardiac or renal
insufficiency without medical advice.6
?Brewer yeast and brewer
cerevisiae)
yeast/Hansen CBS 5926 (Saccharomyces
The simultaneous intake of brewer yeast and antimycotics can decrease the activity
of the brewer yeast. Warning: Simultaneous intake of MAO inhibitors may cause
increased blood pressure.5
?Bromelain (enzyme from pineapple, Ananas comosus)
There may be an increased tendency for bleeding with simultaneous administration of
anticoagulants and inhibitors of thrombocytic aggregation. Plasma and urine levels of
tetracycline may also be increased.5 This herb enhances drug effects: 40-80 mg of
enteric-coated bromelain four times daily with penicillin, chloramphenicol,
erythromycin, or novobiocin, or any combination of these, was associated with lower
morbidity in 53 patients with pneumonia, bronchitis, kidney infections,
staphylococcal infections, infections of the skin, and thrombophlebitis than in patients
using antibiotics alone.25 Bromelain can also improve the efficacy of some
chemotherapy drugs (e.g., 5-fluorouracil and vincristine),26 a possible result of its
fibrinolytic and antitumor effects.11
?Buckthorn bark and berry (Rhamnus frangula)
Long-term use or abuse of buckthorn can increase loss of serum potassium, which
potentiates the toxicity of cardiac glycosides and antiarrhythmic agents (e.g.,
quinidine). Potassium deficiency can be increased by simultaneous use of thiazide
diuretics, corticosteroids, or licorice root.5,6
?Bugleweed (Lycopus europaeus)
Thyroid preparations should not be administered simultaneously with bugleweed.
This herb may interfere with diagnostic procedures involving radioactive isotopes.5
?Bupleurum (Bupleurum falcatum)
Synergistic sedative effects may occur when bupleurum is taken with alcohol,
sedatives, and other central nervous system (CNS) depressants, although no clinical
studies have evaluated this possibility.7
?Cascara sagrada bark (Rhamnus purshiana)
Long-term use or abuse of this herb can increase loss of serum potassium, which
potentiates the toxicity of cardiac glycosides and antiarrhythmic agents (e.g.,
quinidine). Potassium deficiency can be increased by simultaneous use of thiazide
diuretics, corticosteroids, or licorice root.5,6
?Chasteberry fruit or vitex (Vitex agnus-castus)
According to the Commission E,5 interactions were unknown at the time the
monograph was written (1985, revised 1992). Animal experiments have shown
evidence of a dopaminergic effect; therefore, a reciprocal weakening of the effect may
occur if vitex is taken in conjunction with dopamine-receptor antagonists,5 such as
haloperidol. "Possible interactions with dopamine antagonists and dopamine-receptor
blocking agents, such as metoclopramide (widely used as an antiemetic), should also
be considered. As mentioned in other publications on vitex, concomitant
administration with hormone therapy or oral contraceptives is contraindicated. While
vitex is not recommended during pregnancy, its dopaminergic actions also suggest
that it should be avoided during lactation."28
?Chili pepper (Capsicum spp.)
Chili pepper (aka cayenne pepper) protects from the adverse effects of aspirin: chili
pepper [dosage determined relative to capsaicin content] reduced gastric mucosal
damage in 18 subjects when taken 30 minutes before orally administered aspirin.27
?Chinese silk vine root and bark (Periploca sepium)
Previously found as a mislabeled substitute for eleuthero (Eleutherococcus
senticosus), this herb was reported to increase serum digoxin assay levels in a patient
taking conventional cardiac medications.29 Silk vine is a member of the
Asclepiadaceae (milkweed family), members of which are known to contain cardiac
glycosides. However, there are few reports of adverse cardiac effects associated with
this herb.
Cinchona bark (Cinchona pubescens)
This herb increases the effect of concurrently administered anticoagulants.5
?Coffee charcoal (Coffea arabica)
Because of the high absorption capacity of coffee charcoal, the systemic absorption of
simultaneously administered drugs may be reduced.5
Cola nut (Cola nitida)
Cola nut enhances the actions of other caffeine-containing beverages and of
psychoanaleptic drugs.5
Devil claw root (Harpagophytum procumbens)
No interactions have been reported. Because of the protective action of devil claw
against arrhythmia, the possibility of interaction with other antiarrhythmic agents has
been speculated.6
?Eleuthero root (Eleutherococcus senticosus)
Eleuthero (aka Siberian ginseng) can enhance some drug effects; the herb appeared to
increase the efficacy of the antibiotics monomycin and kanamycin in treating Shigella
dysentery and Proteus enterocolitis in a clinical study.30
?Ephedra herb (Ephedra sinica)
Combined with cardiac glycosides or halothane, ephedra can produce cardiac
arrhythmia. Guanethidine enhances the sympathomimetic effect of ephedra. Use with
MAO inhibitors can significantly increase the sympathomimetic action of the alkaloid
ephedrine in the herb,5-7 possibly causing fatal hypertension.7 Use with secale alkaloid
derivatives (e.g., ergotamine), or oxytocin can produce hypertension.5,7
?Eucalyptus leaf and oil (Eucalyptus globulus)
No interactions are known for the leaf. The oil induces the liver enzyme system
involved in detoxification, so the effects of other drugs can be weakened or
shortened.5
?Flaxseed (Linum usitatissimum)
The mucilage in flaxseed may delay the absorption of drugs taken simultaneously;5
for diabetic patients, there may be a delay in glucose absorption.6
?Garlic bulb (Allium sativum)
Garlic may increase bleeding time for patients on warfarin; one report showed that
blood clotting time doubled for two patients taking warfarin and garlic.7,31
?Ginger rhizome (Zingiber officinale)
Ginger may enhance the absorption of sulfaguanidine, according to experiments on
rats.32 Bleeding times and immunological parameters may be influenced because of
ginger ability to inhibit thromboxane synthase and to act as a prostacyclin agonist,
but a clinical study of dried ginger on platelet activity showed no differences in
bleeding times between treatment and placebo groups.33 Large doses (12-14 g) may
enhance the hypothrombinemic effects of anticoagulants, but the clinical significance
of this finding has not been evaluated.7
Ginkgo leaf extract (Ginkgo biloba)
Ginkgo may have an additive effect with other blood-thinning agents: in one patient,
40 mg of a 50:1 concentrated extract, taken twice daily, induced bleeding from the iris
when combined with long-term use of aspirin.34 The results of a clinical study suggest
that in the 20 percent of subjects in whom intracavernosal injection of papaverine to
treat male impotence was ineffective, ginkgo potentiated the action of this drug.35
Ginseng root, Asian (Panax ginseng)
There have been two reports of interactions with the monoamine oxidase inhibitor
phenelzine, but the clinical significance of this interaction has not been evaluated.7
Gurmar leaves (Gymnema sylvestre)
Gurmar, a traditional Ayurvedic herb, can have an additive effect: the hypoglycemic
effects of glyburide and tolbutamide were enhanced in 22 patients with non-insulindependent diabetes by 400 mg/day of a water-soluble, acidic fraction of the ethanolic
extract of gurmar.36 A 400 mg/day dose of the ethanolic extract fraction of gurmar
greatly reduced fasting blood glucose in patients with insulin-dependent diabetes,
which reduced insulin requirements.37
Hawthorn leaf with flower (Crataegus spp.)
Preparations made from flowers with leaves (and possibly also the fruits) may
enhance the effects of cardiac glycosides and have been used with such drugs in
German clinical medicine to reduce the risk of toxic effects. In addition, hawthorn has
been used intermittently with digitalis. Hawthorn procyanidins have reportedly
increased the coronary artery dilatation effect caused by theophylline, caffeine,
papaverine, sodium nitrate, adenosine and epinephrine. Hawthorn has increased
barbiturate-induced sleeping times.19 However, the recently published ESCOP
monograph does not list any interactions, so it is likely that some authorities do not
consider these interactions significant.6
Kava rhizome (Piper methysticum)
Kava may potentiate the effectiveness of substances acting on the central nervous
system, such as alcohol, barbiturates, and psychopharmacological agents.5 An
additive action of kava taken at normal doses for three days with the benzodiazepine
alprazolam led to a lethargic and disoriented state,38 even though an in vitro
experiment showed that kava resin compounds did not bind at benzodiazepine
receptor sites.11 Also, a potential antagonistic or incompatible action may occur: 150
mg kava extract twice daily reduced the efficacy of levodopa in the treatment of
Parkinson disease in one case.39
Licorice root (Glycyrrhiza glabra)
Simultaneous use of licorice with conventional drugs, such as thiazide diuretics, can
increase loss of potassium and result in increased sensitivity to digitalis glycosides.5
Prolonged use in conjunction with thiazide and loop diuretics and cardiac glycosides
is contraindicated, and licorice should not be administered with spironolactone or
amiloride.7
Marshmallow leaf and root (Althaea officinalis)
No interactions are known. Absorption of other drugs taken simultaneously may be
delayed because of high mucilage content.5,6
Milk thistle seed extract (Silybum marianum)
The concentrated extract from the fruits protects the liver from the adverse effects of
simultaneously administered drugs: a dose of 400 mg twice daily helped prevent liver
damage in 15 patients receiving hepatotoxic psychotropic medication, including
butyrophenones and phenothiazines in a clinical trial,40 and reduced the hepatotoxic
effects of phenytoin in a case study.41
Oak bark (Quercus robur)
Absorption of alkaloids and other alkaline drugs may be reduced or inhibited.5
Papain from papaya (Carica papaya)
The enzyme in the green fruit extract may have an additive effect. It increased the
anticoagulant effect of warfarin in one case.42
Peppermint oil (Mentha x piperita)
Patients with achlorhydria (e.g., caused by H2 receptor blocker medication) should
use peppermint oil only in enteric-coated capsules.6
Psyllium, black seed (Plantago afra syn. P. psyllium or P. indica syn. P. arenaria)
This herb may retard the absorption of minerals (such as calcium, iron and zinc),
vitamins (such as vitamin B12) and medicines, especially cardiac glycosides and
coumarin derivatives. Carbohydrate absorption may also be retarded, which could
lead to a reduction in insulin requirement in some diabetic patients; however, this
effect is weak and may need to be considered only in cases of long-term use of bulkforming laxatives.6
Psyllium, blonde seed and blonde seed husk (Plantago ovata)
The Commission E reported that intestinal absorption of other medication taken at the
same time may be delayed.5 Also, absorption of minerals (such as calcium, iron and
zinc), vitamins (such as vitamin B12) and medicines, especially cardiac glycosides
and coumarin derivatives, may be retarded. Carbohydrate absorption may also be
retarded, which could lead to a reduction in insulin requirement in patients with type 1
diabetes;5-7 however, this effect is weak and may need to be considered only in cases
of long-term use of bulk-forming laxatives.6 Decreased bioavailability of other
medications taken simultaneously has been observed: the use of psyllium with lithium
salts may inhibit absorption of lithium in the gastrointestinal tract and hence lead to
lower plasma concentrations.7 One teaspoon (5 ml) of psyllium in water twice daily
reduced the absorption of lithium taken orally in one case, although this effect did not
occur if the lithium was taken one hour or more before the psyllium.12 A decrease in
the rate and extent of carbamazepine absorption has been reported.7
Rhubarb root (Rheum officinale)
With long-term use or abuse, an increase in the effectiveness and toxic effects of
cardiac glycosides and an effect on antiarrhythmics is possible because of the loss of
potassium. Potassium deficiency can be increased by simultaneous use of thiazide
diuretics, corticoadrenal steroids or licorice root.5,7 Decreased intestinal transit time
may reduce the absorption time of orally administered drugs.7
Sarsaparilla root (Smilax spp.)
Absorption of simultaneously administered substances, such as digitalis glycosides or
bismuth, can be increased. Elimination of other substances, such as hypnotics, can be
accelerated. This can increase or decrease the action of herbs taken simultaneously.5
Scotch broom herb (Cytisus scoparius)
Because of its tyramine content, the use of this herb can cause a hypertensive crisis if
it is administered simultaneously with monoamine oxidase inhibitors.5
Senna fruit (pod) and leaf (Cassia senna; also Alexandrian senna, C. senna; C.
acutifolia; and Tinnevelly senna, C. angustifolia)
Long-term use or abuse can increase the loss of serum potassium, which may
potentiate cardiac glycosides and antiarrhythmic agents (e.g., quinidine). Potassium
deficiency can be increased by simultaneous use of thiazide diuretics, corticosteroids
or licorice root.5-7 Decreased intestinal transit time may reduce the absorption time of
some orally administered drugs.7
Stinging nettle leaves (Urtica dioica)
The leaves enhance drug effects: 50 g of stewed leaf (95.5 percent water) enhanced
the anti-inflammatory effect of 50 mg of diclofenac (action equivalent to 200 mg)
when given to 19 patients in a controlled clinical trial.43 This effect was probably due
in part to inhibition of release of tumour necrosis factor-a and interleukin-1b, as
shown when two capsules of an 8:1 or 10:1 extract were given twice daily to 20
healthy volunteers.43
St. John wort herb (Hypericum perforatum)
There are reports of increased serotonin levels in patients using selective serotonin
reuptake inhibitors (e.g., sertraline) with St. John wort.44 Evidence suggests that St.
John wort affects the hepatic cytochrome P450 system, increasing activity of its
most abundant isozyme, CYP3A4, thereby possibly lowering the activity of
simultaneously administered drugs that are known substrates for this isozyme,
including nonsedating antihistamines, oral contraceptives, certain anti-retrovirals,
antiepileptics, calcium channel blockers, cyclosporine, some chemotherapeutics,
macrolide antibiotics, and select antifungals.45,50
Uva ursi or bearberry leaf (Arctostaphylos uva-ursi)
This herb should not be administered with any substances that cause acidic urine, such
as ascorbic acid and ammonium chloride, as it will reduce the antibacterial effect.5,6
Valerian (Valeriana officinalis)
No interactions were reported by the Commission E5 or ESCOP.6 In a clinical study
with the valepotriate fraction, reduction of the adverse effects of simultaneously
administered alcohol was observed, with a dose-dependent increase in the ability to
concentrate.46 A recent monograph review47 cites three older reports of potentiation of
barbiturates.
Willow bark (Salix spp.)
Because of the bark active constituents, there is a theoretical potential for
interactions such as those encountered with salicylates, although no case of this has
been reported in the scientific literature.5 The ESCOP monograph notes that no
interactions have been reported and that irreversible inhibition of platelet aggregation
by aspirin cannot be induced by the structurally different salicin.6
Yohimbe bark (Pausinystalia yohimbe)
Although yohimbe or yohimbine taken by itself can cause hypertension, lower doses
may have a favourable effect in orthostatic hypotension induced by tricyclic
antidepressants.48
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xpanded
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 Results of Combining Herbs and Drugs
1. 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, etc.).
2. 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 side effects.
3. 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.
4. 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.
5. 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 side effects:
Side Effect
Loss of Appetite
Nausea and vomiting
Diarrhea
Fatigue
Numbness in Limbs
Chemo Only
50%
50%
50%
67%
33%
Chemo & Herbal Formula
19%
19%
0%
31%
0%
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) especially 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 herbs but it'
s worth it.
General Rules for Taking Herbs, Vitamins and Drugs:
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 drug cocktail. (Carter, 2004)
Summary
It is generally respectful and beneficial for a holistic practitioner to communicate
about any intended treatment with the prescribing doctor. This is easier if the
practitioner already has contact with the doctor and they have a good working
relationship. There may be situations where this is not the case or where the patient
may not wish there to be any communication with their doctor. This wish must be
respected and it is for the practitioner and the patient to decide how best to continue.
In more difficult cases, it is certainly helpful to seek out advice and support from
more experienced practitioners and from sympathetic conventionally trained
practitioners (Gascoigne, 2003). In summary:
- A holistic practitioner’s main concern is what will benefit the patient.
- Prescribed drugs change symptoms – this may cause confusion when making a
diagnosis.
- A holistic practitioner should enquire about the original condition.
- It is important to study the effects of the drug being taken.
- Patients should be given information about the medication they are taking.
- It is helpful to liaise with sympathetic, conventionally trained practitioners.
References:
Gascoigne, S. (2003). The Prescribed Drug Guide A Holistic Perspective. Jigme Press,
Ireland.
Carter, B (2004). www.the-vu.com
Dharmananda, S. The Interactions of Herbs and Drugs. June, 2001. Institute for
Traditional Medicine. http://www.itmonline.org.
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.