knowledge on interaction between Chinese herbs and drugs

The increasing needs of knowledge on interaction between Chinese herbs and drugs

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. 

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 practicing Chinese medicine 

Two Australian studies 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. 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 contaminations

 Type of Combination

1. Multiple drugs

2. Drugs + single western herbs

3. One drug alone

4. One herb alone

5. Multiple single western herbs

6. Drug + herb formula

7. Single western herb + chinese herb formula

8. Personalized chinese herbal formula alone

Situation and Results

The result of one or more physicians prescribing you one or more drug; interaction range from discomfort to life- threatening.

1 or more physician-prescribed drugs + you buy yourself 1 or more single herbs

Can still have mild to strong side effects Mild side effects are possible

You buy several herbs for yourself and they may interact, especially if the combination is not based on tradition or research

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 its effectiveness

Again based partly on tradition and partly guesswork. Some unexpected interactions are possible but should be mild.

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.

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 non- monograph 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 immune- stimulating 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 22 when consumed as a vegetable concurrently with chlorpropamide in one case report. 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 24 tolerance test produced increased glucose tolerance in nine diabetic outpatients.

?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 yeast/Hansen CBS 5926 (Saccharomyces cerevisiae)

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.

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. 5

This herb may interfere with diagnostic procedures involving radioactive isotopes.

?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-insulin- dependent 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 bulk- forming 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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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.