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The professional literature of Europe and Asia abounds with efficacy and safety studies of many herbal medicines. It is beyond this report's resources to investigate the validity of this vast literature. The following is an overview of some of the more promising research on herbal remedies around the world.
European phytomedicines, researched in leading European universities and hospitals, are among the world's best studied medicines. In some cases they have been in clinical use under medical supervision for more than 10 years, with tens of millions of documented cases. This form of botanical medicine most closely resembles American medicine. European phytomedicines are produced under strict quality control in sophisticated pharmaceutical factories, packaged and labeled like American medicines, and used in tablets or capsules.~Examples of well-studied European phytomedicines include Silybum marianum (milk thistle), Ginkgo biloba (ginkgo), Vaccinium myrtillus (bilberry extract), and Ilex guayusa (guayusa). Their efficacy is well documented. Herbs of American origin, such as Echinacea (purple coneflower) and Serenoa repens (saw palmetto), are better studied and marketed in Europe than in the United States. Below is an overview of recent research on these phytomedicines and American herbs.
• Milk thistle (Silybum marianum). Milk thistle has been used as a liver remedy for 2,000 years. In 1970s studies, seed extracts protected against liver damage and helped regenerate liver cells damaged by toxins (alcohol) and by diseases such as hepatitis (Bode et al., 1977) and cirrhosis (Ferenci et al., 1989). More recently, a 6-month treatment of milk thistle significantly improved liver function in 36 patients with alcohol-induced liver disease (Feher et al., 1990). Animal studies show that it may protect against radiation damage caused by x rays (Flemming, 1971), and it gave "complete protection" to rats against brain damage caused by the potent nerve toxin triethyltin sulfate (Varkonyi et al., 1971). European hospital emergency rooms use intravenous milk thistle extract to counteract cases of liver poisoning ~from toxins such as those in the Amanita phalloides mushroom.
• Bilberry extract (Vaccinium myrtillus). Bilberry extract is believed to help prevent or treat fragile capillaries. Capillary fragility can cause fluid or blood to leak into the tissues, causing hemorrhage, stroke, heart attack, or blindness. Less serious effects include a tendency to bruise easily, varicose veins, poor night vision, coldness, numbing, and leg cramping. Bilberry extract may protect capillaries and other small blood vessels by increasing the flexibility of red blood cell membranes. This action allows capillaries to stretch, increasing blood flow, and red blood cells can deform into a shape that eases their way through narrow capillaries.
European clinical trials have shown the effectiveness of bilberry extract for venous insufficiency of the lower limbs in 18-to 75-year-old subjects (Corsi, 1987; Guerrini, 1987). It has been used to treat varicose veins in the legs, where it significantly improved symptoms of varicose syndrome such as cramps, heaviness, calf and ankle swelling, and numbness (Gatta, 1982). These trials revealed no significant side effects, even at 50 percent over the ~normal dose. In two clinical trials, a standardized bilberry extract was given to 115 women with venous insufficiency and hemorrhoids following pregnancy. Both studies documented improvements of symptoms, including pain, burning, and pruritus, all of which disappeared in most cases (Baisi, 1987; Teglio et al., 1987).
• Ginkgo biloba extract. Though this oriental herb has a different traditional use in Asia, Ginkgo biloba is one of Europe's most lucrative phytomedicines (Duke, 1988). In Europe, ginkgo is used mainly against symptoms of aging. It is believed to stimulate circulation and oxygen flow to the brain, which can improve problem solving and memory. It was shown to increase the brain's tolerance for oxygen deficiency and to increase blood flow in patients with cerebrovascular disease (Haas, 1981). No other known circulatory stimulant, natural or synthetic, has selectively increased blood flow to disease-damaged brain areas. In a French study, "the results confirmed the efficacy of [ginkgo extract] in cerebral disorders due to aging" (Taillandier et al., 1988). In another experiment, those given ginkgo showed consistent and significant improvement over the control group on all tests, including mobility, orientation, communication, mental alertness, recent memory, and other factors (Weitbrecht ~and Jansen, 1985). A "digit copying test" and a computerized classification test confirmed the improved cognitive function related to use of this herb (Rai et al., 1991).
Ginkgo extracts also stimulate circulation in the limbs, reducing coldness, numbness, and cramping. In elderly people, ginkgo improved pain-free walking distance by 30 percent to 100 percent (Foster, 1990). It also lowered high cholesterol levels in 86 percent of cases tested and prevented oxygen deprivation of the heart (Schaffler and Reeh, 1985). The extract seems to affect neurons directly, as shown by a recent French study (Yabe et al., 1992). Another French study proved protection against cell damage, this time by ultraviolet light (Dumont et al., 1992).
A German study documented benefits of long-term ginkgo use in reducing cardiovascular risks, including those associated with coronary heart disease, hypertension, hypercholesterolemia, and diabetes mellitus (Witte et al., 1992). By maintaining blood flow to the retina, ginkgo extracts inhibited deteriorating vision in the elderly. An adequate amount of extract may reverse damage from lengthy oxygen deprivation of the retina. The ~assessment by doctors and patients of the patients' general condition showed a significant improvement after therapy. These results show that visual field damage from chronic lack of blood flow is reversible (Raabe et al., 1991).
• Ilex guayusa (guayusa). In animal studies, a concentrated aqueous herbal preparation from guayusa leaves significantly reduced uncontrolled appetite, excessive thirst, and weight loss associated with diabetes (Swanston-Flatt et al., 1989). Although guayusa's active principles are not established, guayusa contains guanidine, a known hypoglycemic (blood sugar-lowering) substance (Duke, 1992b).
• Echinacea (purple coneflower). The subject of more than 350 scientific studies, most conducted in Europe, Echinacea seems to stimulate the immune system nonspecifically rather than against specific organisms. In laboratory tests, Echinacea increased the number of immune system cells and developing cells in bone marrow and lymphatic tissue, and it seemed to speed their development into immunocompetent cells (cells that can react to pathogens). It speeds their release into circulation, so more are present in blood and lymph, ~and increases their phagocytosis rate--the rate at which they can digest foreign bodies. Echinacea also inhibits the enzyme hyaluronidase, which bacteria use to enter tissues and cause infection. This inhibition helps wounds to heal by stimulating new tissue formation.
Echinacea exhibits interferonlike antiviral activity documented through extensive experiments in Germany. For example, in a double-blind, placebo-controlled study of 180 volunteers, Echinacea's therapeutic effectiveness for treating flu-like symptoms was "good to very good" (Braunig et al., 1992). Another study showed that orally administered Echinacea extracts significantly enhanced phagocytosis in mice (Bauer et al., 1988). Water-soluble Echinacea components strongly activated macrophages (Stimpel et al., 1984), enhanced immune system cell motility, and increased these cells' ability to kill bacteria. Other immune system cells were stimulated to secrete the disease-fighting tumor necrosis factor and interleukins 1 and 6 (Roesler et al., 1991). Another study showed that Echinacea polysaccharides increased the number of immunocompetent cells in the spleen and bone marrow and the migration of those cells into the circulatory system. The authors said these effects resulted in excellent protection of mice against consequences of lethal listeria and ~candida infections (Coeugniet and Elek, 1987).
• Saw palmetto (Serenoa repens). These berries have been used to treat benign prostatic hypertrophy (BPH). The standardized extract was clinically evaluated as effective, has no observed side effects, and costs 30 percent less than the main prescription drug marketed in the United States for BPH (Champpault et al., 1984).
Another effective herbal drug for treating BPH is made from Prunus africanum and is widely prescribed in France. It is interesting to note that the U.S. government is funding a multicenter study on BPH treatment to find the most cost-effective criteria for surgical versus medical treatment. However, because the study includes neither saw palmetto nor Prunus africanum, it may not reflect the "state of the art" in clinical medicine worldwide.
Since the early 19th century, attempts have been made to understand the actions and ~properties of traditional Chinese medicine through scientific research. Nearly all of this work has been conducted during the past 60 years, primarily in laboratories in China, Korea, Japan, Russia, and Germany. It was also during this time that most of the drugs used in modern biomedicine were developed. It is therefore not surprising that most of the biomedical research into the effects and uses of traditional Chinese medicinal substances has attempted to isolate their active ingredients and to understand their effects on body tissues.
Several institutions and laboratories at the forefront of medicinal plant research in China are working to identify and study the active ingredients in traditional Chinese herbal remedies. Researchers at the Institute of Materia Medica in Beijing study the use of herbal remedies to prevent and treat the common cold, bronchitis, cancer, and cardiovascular disease and to prevent conception. The institute has isolated compounds such as bergenin from Ardisia japonica, traditionally used to treat chronic bronchitis, and monocrotaline from Crotalaria sessiliflora, used in folk medicine to treat skin cancer. Most of China's 5,000 medicinal plant species are represented in the institute's herbarium. Other Chinese research organizations with major programs on medicinal herbs are the Institute of Chinese Medicine, Beijing; the ~Institute of Materia Medica, Shanghai; the Institute of Organic Chemistry, Shanghai; the Municipal Hospital of Chinese Traditional Medicine, Beijing; the College of Pharmacy, Nanking; and the Department of Organic Chemistry and Biochemistry, Beijing University (Duke and Ayensu, 1985).
Many herbs in China have been extensively studied by using methods acceptable from a Western perspective. For example, a 1992 article in the Journal of Ethnopharmacology reported that during the preceding 10 years more than 300 original papers on Panax ginseng had been published in Chinese and English (Liu and Xiao, 1992). Ginseng is one of the world's most thoroughly researched herbs. Following is an overview of recent research on ginseng and other herbs in China. Unless otherwise indicated, the data on specific herbs are taken from Chinese Herbal Medicine: Materia Medica, revised edition, compiled and translated by Dan Bensky and Andrew Gamble (1993).
• Ginseng root (Panax ginseng [ren shen]). The Chinese first used oriental ginseng (Panax ginseng) more than 3,000 years ago as a tonic, a restorative, and a specific treatment for ~several ailments. By the 10th century, oriental ginseng had traveled the Silk Road to the Arabic countries (Kao, 1992), and during the next 4 centuries it spread to Europe, where the French, among others, used it to treat asthma and stomach troubles (Vogel, 1970).
In modern times, ginseng has been extensively studied in China, Japan, and Korea and, to a lesser degree, in the United States. In its various forms, ginseng or its compounds have various physiological effects. These include antistress capabilities (Cheng et al., 1986; Yuan et al., 1988), antihypoxia effects (Cheng et al., 1988; Han et al., 1979; Qu et al., 1988), alteration of circadian rhythms by modifying neurotransmitters (Lu et al., 1988; Zhang and Chen, 1987), cardiac performance effects (Chen et al., 1982), protection against myocardial infarction in animals (Chen, 1983; Fang et al., 1986), histamine response effects (Zhang et al., 1988), inhibition of platelet aggregation (Shen et al., 1987; Yang et al., 1988), alteration of circadian variation of plasma corticosterone (Li et al., 1988), modulation of immune functions (Qian et al., 1987; Wang et al., 1980), and delay of the effects of aging (Tong and Chao, 1980; Zhang, 1989).
~ • Fresh ginger rhizome (Zingiber officinale [sheng jiang]). In one study, preparations of sheng jiang and brown sugar were used to treat 50 patients with acute bacillary dysentery. A cure rate of 70 percent was achieved in 7 days. Abdominal pain and tenesmus (an urgent but ineffectual attempt to urinate or defecate) disappeared in 5 days, stool frequency returned to normal in 5 days, and stool cultures were negative within 4 days, with no side effects.
In another study, 6 to 10 thin pieces of sheng jiang placed over the testes were used to treat acute orchitis (inflammation of the testicles). The ginger was changed daily or every other day. All participants felt a hot-to-numbing sensation in the scrotum, while a few reported local erythema and edema. Among 24 patients in the study, average cure time was 3 days. In a control group of four patients, average healing time was 8.5 days. This technique is not recommended for patients with scrotum lesions.
• Chinese foxglove root (Rehmannia glutinosa [sheng di huang]). A preparation of this herb and Radix glycyrrhiza uralensis (gan cao) was used to treat 50 cases of hepatitis in ~various stages. Within 10 days, 41 cases showed improved symptoms, reduced liver and spleen size, and improved liver function tests. Experiments from the 1930s seemed to show that sheng di huang, given to rats via gastric lavage or injection, lowered serum glucose levels. Later studies of this problem showed variable results. Work in Japan showed that the herb is useful in treating experimental hyperglycemia in rats. In other studies, decoctions of sheng di huang have been used to treat rheumatoid arthritis in adults and children. In one uncontrolled study, 12 subjects all showed reduced joint pain and swelling, increased function, improved nodules and rash, and lowered temperature. Followup over 3 to 6 months showed only one relapse, which was treated successfully with the same preparation.
• Baical skullcap root (Scutellaria baicalensis [huang qin]). Huang qin was shown to inhibit the skin reaction of guinea pigs to passive allergic and histamine tests. It has been shown to be effective in treating guinea pigs with allergic asthma. Huang qin also prevented pulmonary hemorrhage in mice subjected to very low pressure. Huang qin has an inhibitory effect against many kinds of bacteria in vitro, including Staphylococcus aureus, Corynebacterium diphtheriae, Pseudomonas aeruginosa, Streptococcus pneumoniae, and ~Neisseria meningitidis. In one report, one strain of bacteria (Staph. aureus) that was resistant to penicillin remained sensitive to this herb. According to one study, 100 patients with bacillary dysentery received a prescription composed mainly of huang qin. Mean recovery times were 2.5 days until symptoms disappeared, 3.3 days until normal stool examination, and 4.3 days until negative stool cultures.
• Coptis rhizome, or yellow links (Coptis chinensis [huang lian]). Huang lian and one of its active ingredients, berberine, have broad effects in vitro against many microbes. It strongly inhibits many bacteria that cause dysentery; it is more effective than sulfa drugs but less effective than streptomycin or chloramphenicol. Decoctions of huang lian have been effective against some bacteria that developed resistance to streptomycin and other antibiotics. The herb's antimicrobial ingredient is generally considered to be berberine. Experiments on chicken embryos show that huang lian has an inhibitory effect against flu viruses and the Newcastle virus.
Huang lian preparations have a strong inhibitory effect in vitro against many pathogenic ~fungi. Capsules of powdered huang lian were given to patients with typhoid fever, with good results. In one report, two cases that were resistant to antimicrobials responded to this herb. In another study, 30 cases of pulmonary tuberculosis were treated with huang lian for 3 months; all improved.
A 10-percent solution of huang lian also was used to treat 44 cases of scarlet fever. It was as effective as penicillin or a combination of penicillin and a sulfa drug. Huang lian also has been successfully used to treat diphtheria; in one study, the fever subsided in 1 to 3 days. Huang lian ointments or solutions promoted healing and reduced infections in first-and second-degree burns. It also has positive effects on blood pressure, smooth muscle, lipid metabolism, and the central nervous system; is effective as an anti-inflammatory; and has been used successfully in gynecology, ophthalmology, and dermatology patients.
• Woad leaf (Isatis tinctoria [da qing ye]). Da qing ye kills some kinds of bacteria, including some strains resistant to sulfa drugs. It was reported effective in hundreds of cases of encephalitis B, with cure rates of 93 percent to 98 percent. In most cases the fever ~subsided in 1 to 4 days, and symptoms disappeared 3 to 5 days later. Da qing ye has been effective by itself in mild and moderate cases; other herbs, acupuncture, and Western drugs should be added in severe cases.
In a study of 100 subjects, only 10 percent of the group given a da qing ye decoction twice daily had upper respiratory infections during the study period versus 24 percent of the control group. When a mixture of decoctions of da qing ye and Herba taraxaci mongolici cum radice (pu gong ying) was given to 150 children with measles, signs and symptoms disappeared in 4 to 5 days. In 68 of 100 cases, da qing ye was used successfully to treat infectious hepatitis.
• Wild chrysanthemum flower (Chrysanthemum indicum [ye ju hua]). Ye ju hua has been used to treat hypertension, either alone as an infusion or with Elos lonicerae japonicae (jin yin hua) and Herba taraxaci mongolici cum radice (pu gong ying) in a decoction. Ye ju hua preparations have an inhibitory effect in vitro against some bacteria and viruses. Preparations given orally or as injections lowered blood pressure. Preparations made from the whole ~plant had more toxicity and less efficacy than those made from the flower alone.
One study was performed with 1,000 subjects to see whether ye ju hua would prevent colds. The subjects were compared with their own histories and against a matched set of 261 controls. A ye ju hua decoction was taken once a month by people with histories of infrequent colds, twice a month by those with three to five colds a year, and weekly by those with frequent colds. Comparison with their own histories showed a 13.2-percent reduction in frequency, but a greater frequency in comparison with the controls. At the same time, another clinical series of 119 cases of chronic bronchitis was observed. Using the same preparation, this group experienced a 38-percent reduction in acute attacks in comparison with their seasonally adjusted rate for the previous year.
• Bletilla rhizome (Bletilla striata [bai ji]). Bai ji, in powdered form or in a powder made from starch and a decoction of bai ji, helped control bleeding in seven of eight cases of surgical wounds to dogs' livers. Pure starch was much less effective. Similar results have been achieved with sponges soaked in a sterile water-extraction solution of the herb. In ~anesthetized dogs with 1-mm-diameter stomach perforations, washing the perforations with 9 g of powdered bai ji through a tube closed the perforations in 15 minutes. Eight hours after the procedure the abdomens were opened, and no trace of gastric contents was found. When the dogs' stomachs were full or the perforations were larger, powdered bai ji had no effect.
In another study, powdered bai ji was used to treat 69 cases of bleeding ulcers, and in all cases the bleeding stopped within 6.5 days. In another series of 29 perforated ulcer cases, the powdered herb was successful in 23 cases, 1 required surgery, and the other 4 died (1 went into hemorrhagic shock while under treatment, and the other 3 were in precarious condition on admission).
In other studies, powdered bai ji was given to 60 chronic tuberculosis patients who had not responded to normal therapy. After taking the herb for 3 months, 42 were clinically cured, 13 significantly improved, and 2 showed no change. A sterile ointment made from decocted bai ji and petroleum jelly was used in a local application to treat 48 cases of burns ~and trauma (less than 11 percent of total body area). Dressings were changed every 5 to 7 days, and all patients recovered within 1 to 3 weeks.
• Salvia, or cinnabar root (Salvia miltiorrhiza [dan shen]). Dan shen caused coronary arteries to dilate in guinea pig and rabbit heart specimens. In one study of 323 patients given a dan shen preparation for 1 to 9 months, there was marked improvement in 20.3 percent of clinical cases and general improvement in 62 percent of cases. Results were best when patients had coronary artery disease and no history of myocardial infarction. In a clinical series of more than 300 patients with angina pectoris, a combination of dan shen and Lignum dalbergiae odoriferae (jiang xiang) given intramuscularly or intravenously improved symptoms in 82 percent and electrocardiograms in 50 percent of cases.
• Corydalis rhizome (Corydalis yanhusuo [yan hu suo]). Yan hu suo is widely used to treat pain. Powdered yan hu suo is a very strong analgesic, about 1 percent the strength of opium. In one clinical study of 44 patients with painful or difficult menstruation, 50 mg of the yan hu suo active ingredient, dihydrocorydaline, given 3 times a day brought significant relief ~in 14 cases and reduced pain in another 18 cases. Side effects included reductions in menstrual flow, headaches, and fatigue.
• Root of Szechuan aconite (Aconitum carmichaeli [fu zi]). Fu zi's toxicity has always been a major concern. It is usually prepared with salt to reduce its toxicity. Anesthetized dogs or cats given fu zi preparations showed a sharp drop in blood pressure. In another experiment, fu zi caused blood vessels to dilate in lower extremities and coronary vessels. In normal dosage for humans, fu zi slightly lowers blood pressure, while a large overdose can cause rapid heartbeat or ventricular fibrillation. This herb seems to have some cardiotonic function and a regulatory effect on heart rhythm. Administered with herbs such as Cortex cinnamomi cassiae (rou gui), Panax ginseng (ren shen), Rhizoma zingiberis officinalis (gan jiang), and Radix glycyrrhiza uralensis (gan cao), fu zi raised blood pressure in animals with acute hemorrhage. In one study, patients with congestive heart failure were treated by intramuscular injections of a fu zi preparation. In all cases, including one of cardiogenic shock, the result was increased cardiac output as well as decreased breathing difficulty, liver swelling, and general edema. A few cases showed temporary side effects of flushing and ~slight tremors.
• Licorice root (Glycyrrhiza uralensis [gan cao]). Gan cao preparations have been used with common antituberculosis drugs in many large clinical studies among patients who did not respond to standard treatment. In most cases, symptoms improved or disappeared and x rays improved markedly. In many clinical studies using gan cao for ulcers with groups of 50 to 200 subjects, effectiveness was around 90 percent. It was especially useful to treat the pain, which disappeared or improved within 1 to 3 weeks. The more recent the onset of disease, the better the results. In almost all cases the powdered herb was most effective.
In rats with experimentally induced atherosclerosis, gan cao lowered cholesterol levels and stopped progression of lesions. In several experiments, the herb reduced the toxicity of some substances, including cocaine, and moderately reduced the toxicity of others, including caffeine and nicotine. When decocted with fu zi, it sharply reduced fu zi's toxicity.
• Dryopteris root, or shield fern (Dryopteris crassirhizoma [guan zhong]). Dryopteris ~crassirhizoma is called dong bei guan zhong because it is found in northeastern (dong bei) China. In recent times this herb has been prescribed as a preventive measure during influenza epidemics. Guan zhong preparations strongly inhibit the flu virus in vitro. In one clinical trial, 306 people took twice-weekly doses of guan zhong and 340 served as controls. In the treatment group, 12 percent became ill versus 33 percent of the controls. Local versions of guan zhong from Guangdong, Hunan, and Jiangxi provinces have mildly inhibitory effects in vitro against many pathogenic bacteria. Guan zhong also is effective against pig roundworms in vitro, and it expels tapeworms and liver flukes in cattle.
In other studies, decoctions and alcohol extracts of dong bei guan zhong strongly stimulated the uterus of guinea pigs and rabbits. It increased the frequency and strength of contractions. Intramuscular injections of dong bei guan zhong preparations were used with more than 91-percent success to treat postpartum, postmiscarriage, and postsurgical bleeding.
• Garlic bulb (Allium sativum [da suan]). Da suan preparations have a strong inhibitory ~effect in vitro against amebae. In one study, concentrated da suan decoctions were used to treat 100 cases of amebic dysentery. The cure rate was 88 percent, and the average hospital stay was 7 days. In this clinical study, purple-skinned bulbs were more effective than white-skinned bulbs. Patients were discharged on a regimen that included purple-skinned da suan in the daily diet.
When used with Chinese leek seeds, da suan juice and decoctions have a strong inhibitory effect in vitro against many pathogenic bacteria. Da suan can be effective against bacteria that resist penicillin, streptomycin, and chloramphenicol. In one clinical study, 130 patients with bacillary dysentery were given da suan enemas. Of the followup colonoscopies, 126 showed that pathological changes were resolved within 6.3 days. In other studies with hundreds of patients, da suan's effectiveness against bacillary dysentery was more than 95 percent. Again, purple-skinned garlic seemed more effective than white-skinned, and fresh bulbs were more effective than old ones. In one clinical study, 17 cases of encephalitis B were treated with an intravenous drip of da suan preparations and supportive care. Except for one fatality, all other cases recovered.~India
Ayurveda, the oldest existing medical system, is recognized by WHO and is widely practiced. The word comes from two Sanskrit roots: ayus means life or span; veda means knowledge or science. India recently increased research on traditional Ayurvedic herbal medicines after observations that they are effective for conditions to which they have traditionally been applied. For example, the ancient Sanskrit text on Ayurveda, the Sushruta Samhita, noted that Commiphora mukul was useful in treating obesity and conditions equivalent to hyperlipidemia, or increased concentrations of cholesterol in the body. The plant has been used by Ayurveda practitioners for at least 200 years and may have been in use since the writing of the Sushruta Samhita more than 2,000 years ago. In a recent study, the crude gum from Commiphora mukul significantly lowered serum cholesterol in rabbits with high cholesterol levels. The plant substance also protected rabbits from cholesterol-induced atherosclerosis (hardening of the arteries). This finding led to pharmacological and toxicological studies that showed this herbal remedy to be effective in humans, with no adverse side effects. Approval was obtained from the national regulatory authority in India for further clinical trials (Verma and Bordia, 1988). The drug is marketed in India and other countries for treatment of hyperlipidemia (Chaudhury, 1992).
The following other Ayurvedic herbs have recently been studied in India under modern scientific conditions:
• Eclipta alba. In Ayurvedic medicine, Eclipta alba is said to be the best drug for treating liver cirrhosis and infectious hepatitis. Eclipta alba and Wedelia calendulacea are widely used in India for jaundice and other liver and gall bladder ailments. One recent study showed that a liquid extract from fresh Eclipta leaves was effective in vivo in preventing acute carbon tetrachloride-induced liver damage in guinea pigs. Clinically, the powdered drug is effective against jaundice in children (Wagner et al., 1986).
• Common teak tree (Tectona grandis). Trunk wood and bark of the common teak tree are described in Ayurvedic medicine as a cure for chronic dyspepsia (indigestion) associated with burning pain. Teak bark forms an ingredient of several Ayurvedic preparations used to ~treat peptic ulcer. Pandey et al. (1982) experimentally screened teak bark and its effect on gastric secretory function and ulcers in albino rats and guinea pigs. The solution reduced gastric ulcers in restrained albino rats and significantly inhibited gastric and duodenal ulcers in guinea pigs.
• Indian gooseberry (Emblica officinalis [amla]). Jacob et al. (1988) studied the effect of total serum cholesterol by using amla to supplement the diets of normal and hypercholesterolemic men aged 35-55. The supplement was given for 28 days in raw form. Normal and hypercholesterolemic subjects showed decreased cholesterol levels. Two weeks after the supplement was withdrawn, total serum cholesterol levels of the hypercholesterolemic subjects rose almost to initial levels.
• Picrorhiza kurroa. P. kurroa rhizomes are main ingredients of a bitter tonic used in fever and dyspepsia (indigestion). This drug occupies a prestigious position in Ayurveda. It often substitutes for Gentiana kurroo, the Indian gentian. Powdered rhizomes also are used as a remedy for asthma, bronchitis, and liver diseases. Other researchers have reported that a P. ~kurroa-derived mixture called kutkin exhibits hepatoprotective activity; that P. kurroa acts as a bile enhancer; that it has antiasthmatic effects in patients with chronic asthma; and that it has immunomodulating activity in cell-mediated and humoral immunity. Another study (Bedi et al., 1989) shows that P. kurroa works to boost the immune system as a supplement to other treatments in patients with vitiligo, a skin disease that causes discolored spots.
• Articulin-F. This herbomineral formula contains roots of Withania somnifera, stem of Boswellia serrata, rhizomes of Curcuma longa, and a zinc complex. Kulkarni et al. (1991) performed a randomized, double-blind, placebo-controlled crossover study of articulin-F to treat osteoarthritis, a common progressive rheumatic disease characterized by degeneration and eventual loss of articular cartilage. Articulin-F treatment produced a significant drop in pain severity and disability score, whereas radiological assessment showed no significant changes.
• Abortifacient plants. Nath et al. (1992) organized a survey program in Lucknow and Farrukhabad, two towns in Uttar Pradesh, India, from March to July 1987. During the ~survey, they recorded the common folk medicine used by women and consulted Ayurvedic and Unani drug encyclopedias for the antireproductive potential of the following medicinal plants: leaves of Adhatoda vasica, leaves of Moringa oleifera, seeds of Butea monosperma, seeds of Trachyspermum ammai, flowers of Hibiscus sinensis, seeds of Abrus precatorius, seeds of Apium petroselinium, buds of Bambusa arundensis, leaves of Aloe barbadensis, seeds of Anethum sowa, seeds of Lepidium sativum, seeds of Raphanus sativus, seeds of Mucuna pruriens, seeds of Sida cordifolia, seeds of Blepharis edulis, flowers of Acacia arabica, and seeds of Mesua ferrea. Plant materials were collected, authenticated, chopped into small pieces, air dried in shade, and then ground to a 60-mesh powder. During the survey, female rats were given aqueous or 90-percent ethanol extracts of the plants orally for 10 days after insemination by males, with special attention to effects on fetal development. Leaf extracts of Moringa oleifera and Adhatoda vasica were 100-percent abortive at doses equivalent to 175 mg/kg of starting dry material.
• Neem (Azadiractica indica) and turmeric (Curcuma longa). In the Ayurveda and Sidha systems of medicine, neem and turmeric are used to heal chronic ulcers and scabies. Charles ~and Charles (1991) used neem and turmeric as a paste to treat scabies in 814 people. Ninety-seven percent of cases were cured within 3 to 15 days. The researchers found this to be a cheap, easily available, effective, acceptable mode of treatment for villagers in developing countries, with no adverse reactions.
• Trikatu. Trikatu is an Ayurvedic preparation containing black pepper, long pepper, and ginger. It is prescribed routinely for several diseases as part of a multidrug prescription. These herbs, along with piperine (alkaloid of peppers), have biological effects in mammals, including enhancement of other medicaments. Of 370 compounds listed in the Handbook of Domestic Medicines and Common Ayurvedic Remedies (Handbook, 1979), 210 contain trikatu or its ingredients. Trikatu is a major decoction used to restore the imbalance of kapha, vata, and pitta, the body's three humors (see the "Alternative Systems of Medical Practice" chapter). Piper species are used internally to treat fevers, gastric and abdominal disorders, and urinary difficulties. Externally they are used to treat rheumatism, neuralgia, and boils. P. longum and P. nigrum are folklore remedies for asthma, bronchitis, dysentery, pyrexia, and insomnia (Akamasu, 1970; Chopra and Chopra, 1959; Perry, 1980; ~Youngken, 1950). In Chinese folklore, P. nigrum is mentioned as a treatment for epilepsy (Pei, 1983). The efficacy of P. longum fruits in reducing asthma in adults (Upadhyaya et al., 1982) and children has been reported (Dahanukar et al., 1984). P. nigrum promoted digestive juice secretion (Shukla, 1984) and increased appetite (Sumathikutty et al., 1979). P. longum was reported useful in patients with gastric disorders accompanied by clinical symptoms of achlorhydria (Kishore et al., 1990).
In 1977 and 1978, Croom (see Kirkland et al., 1992) spent 2 years documenting plant remedies among the Lumbee Indians, the largest group of Native American Indians east of the Mississippi River. Following are some often-used medicinal plant remedies of the Lumbee:
• Rabbit tobacco (Gnaphalium obtusifolium). These annual herbs reach a height of 1 to 3 feet and have erect stems with brown, shriveled leaves persisting into winter and stems ~covered with feltlike hairs in summer. The leaves are 1 to 3 inches long, and alternate. The flowers, minute in whitish heads, appear in late summer to fall. Fields, pastures, and disturbed areas are the sites of this common native plant of the eastern United States. It is used to treat colds, flu, neuritis, asthma, coughs, and pneumonia. This is one of the most popular plants used by the Lumbee. The decoction is drunk hot, like most medicinal teas, and is said to cause profuse sweating.
• Poke (Phytolacca americana). Also a common native plant of the eastern United States, poke is a robust, perennial herb that reaches a height of 9 feet. It has a large white root; a green, red, or purple stem; alternate leaves up to 1 foot long; and white flowers in a drooping raceme. The fruit is a dark purple to black berry, round, soft, and juicy. Poke is found in waste areas, road sides, disturbed habitats, fields, and pastures. It is used to treat asthma, spring tonic, boils (risings), sores, intestinal worms in people or chickens, cramps, and stomach ulcers. Poke is said to inhibit gram-positive and gram-negative bacteria and is listed as a parasiticide in the British Herbal Pharmacopoeia.
~ • Pine (Pinus echinata, P. palustris, P. virginiana). Pines are resinous evergreen trees with needlelike foliage leaves in bundles of two to five. The male and female reproductive structures are in separate cones on the same tree; the female cone matures to a large woody cone with winged seeds; pollen sheds in the spring. Pine is used to treat colds, flu, pneumonia, fever, heartburn, arthritis, neuritis, and kidney problems.
• Oak (Quercus laevis, Q. phellos). These deciduous trees have alternate, unlobed, or variously lobed leaves and minute flowers; the fruit is an acorn. Oak is used to treat kidney problems (including Bright's disease), bladder problems, virus, menstrual bleeding, diarrhea, sores, sprains, and swellings. It is also used as a booster for other remedies.
• Sassafras (Sassafras albidum). These deciduous, aromatic, small trees or shrubs have green twigs and--when mature--thick, furrowed bark. The leaves are 2.5 to 5 inches long; alternate; and either unlobed, lobed on one side, or three-lobed. Flowers are small and yellow in clusters at the end of twigs. The fruit is a dark blue, fleshy drupe on a bright red stalk and cup. This common native plant of fencerows, woodland borders, and old fields of ~the eastern United States is used to treat measles, chicken pox, colds, flu, and fever. It is also used as a "shotgun heart remedy," a blood purifier, and a spring tonic.
According to the Handbook of Northeastern Indian Medicinal Plants Native American Indians used about 25 percent of the flora of Maryland for medicinal purposes (Duke, 1986). A few examples of medicinal plant species in Maryland are as follows:
• Sweetflag or calamus (Acorus). The root has been used to treat flatulence, colds, coughs, heart disease, bowel problems, colic, cholera, suppressed menses, dropsy, gravel, headache, sore throat, spasms, swellings, and yellowish urine. Some tribes considered the root a panacea; others thought it had mystic powers.
• Bloodroot (Sanguinaria). This very poisonous plant is emetic, laxative, and emmenagogue. It has been used to treat chronic bronchitis, diphtheria, sore throat, uterine and other cancers, tetterworm, deafness, and dyspepsia; it has also been used as a pain reliever and sedative. In Appalachia it is carried as a charm to ward off evil spirits.~ • Yellowdock. Contains anthraquinones of value in the treatment of ringworm and some types of psoriasis. Rumicin from the roots reportedly destroys skin parasites. The anthraquinones are proven laxatives.
• Coneflower (Echinacea, Rudbeckia). Echinacea (purple coneflower) reportedly increases resistance to infection, bad coughs, dyspepsia, venereal disease, insect bites, fever, and blood poisoning.
• Witch hazel. A proven astringent and hemostat (to stop bleeding).
• Lobelia (Lobelia cardinalis). Cardinal flower was used to indurate ulcers and to treat stomachache, syphilis, and worms. The leaf tea was used for cold, croup, epistaxis (nosebleed), fever, headache, rheumatism, and syphilis. Lobelia inflata (Indian tobacco) yields lobeline sulfate, used in antitobacco therapy. It is used as an antiasthmatic, an expectorant, and a stimulant for bronchitis; it also is used to treat aches, asthma, boils, croup, colic, sore throat, stiff neck, and tuberculosis of the lungs. Some smoked the herb to ~break a tobacco habit.
• Mayapple (Podophyllum peltatum). Early Native American Indians used the roots as a strong purgative, liver cleanser, emetic, and worm expellant. A resin made from the plant has been used to treat venereal warts and exhibits antitumor activity; it also is used for snakebite and as an insecticide for potato bugs.
• Wild cherry (Prunus virginiana). The bark has been used to treat sores and wounds, diarrhea, cold and cough, tuberculosis, hemoptysis, scrofula, sore throat, stomach cramps, and piles. Native American Indians treated snow blindness by leaning over a kettle of boiling bark "tea." Some smoked the bark for headache and head cold.
• White willow (Salix alba). The bark is astringent, expectorant, hemostatic, and tonic. It is used to treat calluses, cancers, corns, tumors, and warts. Salicylic acid (used to make aspirin) is found in white willow. Leaves and bark of different willows are used in a tea to break a fever. Some Native American Indians burned willow stems and used the ashes to treat sore eyes.