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Herbal Medicine

Herbal Medicine

Using medicines derived from plants is a practice probably as old as humankind itself. Prehistoric peoples likely noted when consuming a particular plant part provided relief, such as willow bark "tea" lowering a fever. Sumatran clay tablets engraved forty centuries ago list plant-based remedies for common ills, as do ancient writings from Egypt and China. In nineteenth-century United States, St. John's wort and Echinacea were just two of many commonly used herbal remedies.

Many modern medicines are synthetic versions of plant-derived "natural products." A compound from a periwinkle plant, for example, served as the basis for a powerful drug that fights leukemia. Poppies provide alkaloids such as morphine that are potent painkillers.

In the U.S. today, one-third of all adults have tried herbal treatments, creating a multibillion-dollar market. The resurgence of interest in herbal medicine is largely due to the Dietary Supplements Health and Education Act (DSHEA) of 1994, which expanded the definition of "dietary supplement" beyond essential nutrients to include "herbs and botanicals," thus removing them from regulation as drugs. This designation means that labels can only mention ways that the herbal product can promote health, not cure disease. For example, valerian root "promotes restful sleep," St. John's wort "may help enhance mood," and Echinacea and goldenseal "may help support the immune system." Table 1 lists some herbal products marketed as food supplements that are currently being tested for efficacy in treating specific illnesses. Many physicians and biochemists argue that active ingredients in many herbal remedies are indeed drugs, and should be regulated as such.

The U.S. Food and Drug Administration does not require food supplements to be tested for safety and efficacy in treating illness, or even that a product be consistent in concentration of the active ingredient, or the plant part from which it is derived. Two-thirds of individuals who take herbal supplements do so without consulting a physician, which can be dangerous. St. John's wort, for example, interacts with enzymes that control blood levels of many drugs, including anesthetics and drugs that transplant recipients must take. Some herbal supplements may be dangerous if taken in large

Herbal Supplements and Conditions They Treat
Product Condition
Cannabis migraine
Echinacea respiratory infection
Garlic cardiovascular disease
Ginger root nausea and vomiting
Ginkgo biloba memory impairment
  intermittent claudication
  glaucoma
  tinnitus
  altitude sickness
Horse chestnut chronic venous insufficiency
Kava anxiety
Oregon grape psoriasis
Red clover elasticity of large arteries
Red grape juice coronary artery disease
Saw palmetto frequent urination due to enlarged prostate
Valerian root insomnia
Willow bark lower back pain

doses or by individuals with particular illnesses. For example, Ginkgo biloba has been linked to intracranial bleeds, and Ephedra to seizures, hypertension, stroke, and death.

Studies to test effects of herbal substances may be flawed or yield inconsistent results. Some reports are actually studies of studies, selected in a way that prejudices the results. Many trials are too small or not well enough controlled to yield meaningful conclusions. Consider an investigation on whether fruits of the chastetree can prevent symptoms of premenstrual syndrome. For three months, 1,634 women took two capsules a day of the extract, and reported their symptoms before and after the trial periodwith no control group not receiving the drug. For St. John's wort, one large investigation found it to be just as effective as a standard antidepressant drug, yet another large study published a few months later found it to be useless.

Not all herbal remedies lack scientific backing due to the peculiarities of regulatory law or variations in experimental design. For example, people have drunk cranberry juice to ease symptoms of urinary tract infections for many years. The effect was thought to be due to increasing acidity of urine, but a 1998 study found that compounds called proanthocyanidins prevent bacterial outgrowths from adhering to the wall of the uterine tract.

It is wise to consult a physician when considering use of an herbal product. Even for a well-understood remedy such as cranberry extract, additional therapy may be required, or drug interactions a possibility. The law may not currently consider herbal ingredients to be drugs, but science indicates otherwise.

see also Clinical Trials; Ethnobotany; Psychoactive Drugs; Secondary Metabolites in Plants

Ricki Lewis

Bibliography

Attenborough, David. The Private Life of Plants. Princeton, NJ: Princeton University Press, 1995.

Fleming, G. Alexander. "The FDA, Regulation, and the Risk of Stroke." The New England Journal of Medicine 343, no. 25 (21 December 2000): 18861887.

Shelton, Richard C., et al. "Effectiveness of St. John's Wort in Major Depression." The Journal of the American Medical Association 285, no. 15 (18 April 2001): 19781986.

Simpson, Beryl Brintnall, and Molly Conner Ogorzaly. Economic Botany: Plants in Our World, 3rd ed. New York: McGraw-Hill Higher Education, 2000.

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herbal medicine

herbal medicine Plants have been used for medicinal purposes for as long as history has been recorded. China, India, Egypt, and Assyria appear to have been the places which cradled the use of herbs, but herbalism was common in Europe by medieval times. Despite the progress in orthodox medicine, interest in alternative medicine, including herbalism, is on the increase in the West — and for 80% of the world herbal medicine is still the only kind to which ordinary persons have ready access.

A great variety of plants are used for medicinal treatments. Either the dried plant, or a specific part of it (root, leaves, fruit, flowers, seeds), is formulated into suitable preparations — compressed as tablets or made into pills, used to make infusions (teas), extracts, tinctures, etc., or mixed with excipients to make lotions, ointments, creams, etc. Few herbal drugs are subject to legislative control. Obviously control is needed for poppy capsules (which contain opium), belladonna, digitalis, nux vomica beans (which contain strychnine), and rauwolfia (which contains reserpine). Most herbal remedies are freely available, although rarely have any been investigated with the thoroughness of orthodox medicines. The claims made for many herbal remedies are for trivial or minor ailments, due partly to the strictures put on legal claims for efficacy, and partly because herbalists claim to treat the whole person to restore normal physiological balance, rather than to treat or cure a particular medical illness. Activities of herbal medicines are often described in very general terms — such as carminative, laxative, demulcent, antitussive, expectorant, sedative, antiseptic, or astringent. Unlike orthodox medicines, which usually consist of a single, isolated principle often synthetic), plants or extracts of plants contain multiple constituents, not all of them active. Herbalists often claim that the admixture of multiple constituents leads to synergism between the active moieties. Similarly, many consider that since plants are natural materials they are safer and will produce fewer side-effects than synthetic drugs. There is little substance or reason in either of these claims. For example, comfrey (Symphytum officinale) is considered a safe herb and is used as a demulcent. However, it contains pyrrolizidine alkaloids, which are toxic to the liver and can cause liver cancer. Media attention can often cause a major increase in the demand and use of herbal drugs — for example, evening primrose oil, feverfew, Ginko biloba, and ginseng. One of the problems with herbal drugs, especially those with active principles which have well-defined medicinal effects (e.g. digitalis), is that the amount of active principle(s) varies according to the location where the plant is grown, the prevailing weather conditions, etc., so it is vital in these instances that the crude material is assayed appropriately so that the dosage can be accurately controlled, especially where the therapeutic ratio is low. (Therapeutic ratio is the ratio of the dose causing toxic effects to that required for treatment.)

From time to time new drugs are discovered from herbal sources — for example, taxol, derived from the yew, is an important drug for some forms of cancer. The active principle is extracted and purified from plant material for as long as that process remains economically viable compared with chemical synthesis.

Alan W. Cuthbert

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herbal medicine

herbal medicine, use of natural plant substances (botanicals) to treat and prevent illness. The practice has existed since prehistoric times and flourishes today as the primary form of medicine for perhaps as much as 80% of the world's population. Over 80,000 species of plants are in use throughout the world. Along with acupuncture, herbal medicine is considered primary health care in China, where it has been in documented use for over 2,500 years.

Herbs may be used directly as teas or extracts, or they may be used in the production of drugs. Approximately 25% of the prescription drugs sold in the United States are plant based. Many more herbal ingredients are present in over-the-counter drugs, such as laxatives. Medicines that come from plants include aspirin from willow bark (Salix species) and digitalis from foxglove (Digitalis purpurea).

Scientific interest in herbal medicine in the United States has lagged behind that in the countries of Asia and W Europe; in Germany, for example, one third of graduating physicians have studied herbal medicine, and a comprehensive therapeutic guide to herbal medicines has long been published there. Nonetheless, millions of people in the United States use herbal products to treat a wide variety of ailments or to enhance health. Among the more popular remedies used are ginseng, to increase stamina and as a mild sedative; St.-John's-wort, for mild depression; echinacea, to aid the immune system and alleviate colds; kava, to calm anxiety and treat insomnia; saw palmetto, for enlarged prostate; and ginkgo biloba, to improve short-term memory (see ginkgo). Some people have used botanicals in an attempt to stave off serious illnesses such as AIDS.

This widespread use has prompted demands that herbal remedies be regulated as drugs to insure quality standards. The U.S. Food and Drug Administration (FDA) can require a clinical trial on any herb that has a health claim on its label, but medical testing, which is geared toward observing a particular active component, is difficult to apply to herbs, which may have many interacting ingredients. Debate over botanicals' validity and safety as medicines and over the appropriate degree of government regulation continues. The Dietary Supplement Health and Education Act, passed in 1994, reclassified herbs as dietary supplements rather than food additives. It forbids unreasonable health claims by the manufacturers, but makes it the FDA's responsibility to prove that a marketed product is unsafe. (In contrast, in prescription and over-the-counter drugs, it is the manufacturer's responsibility to prove safety and effectiveness before a drug can be marketed.)

Another concern surrounding herbal medicine is the availability of wild plants for a growing market; it is feared that the limited supplies of known wild herbs are being threatened by overharvesting and habitat loss. The potential of isolating beneficial drugs from plants, however, has prompted large pharmaceutical companies to contribute to the conservation of the tropical rain forest. Biologists have called for more careful study of medicinal plants, especially regarding their capacity for sustainable harvesting and the effects of cultivation on their efficacy as medicaments.

See V. E. Tyler and S. Foster, Tyler's Honest Herbal (rev. ed. 1999); The Physicians' Desk Reference for Herbal Medicines (annual).

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Herbal Medicine

Herbal Medicine

Resources

Modern medicine has provided many breakthrough treatments for serious diseases. Some conditions, however, have eluded the healing grasp of contemporary western medicine, which emphasizes rigorous scientific investigation of therapies. In addition, rising costs of some treatments have placed modern healthcare beyond the reach of many people. The drugs that routinely fill pharmacy shelves of post-industrialized nations remain inaccessible to the majority of the people in the world. Instead, populations in many areas of the globe use herbal medicine, also called botanical medicine or phytotherapy, as the principal means of healthcare. Herbal medicine is the use of natural plant substances to treat illness. In fact, the World Health Organization (WHO) of the United Nations estimates that as much as 80% of the world population relies on the use of various forms of traditional (herbal) medicine for its primary healthcare.

Based upon hundreds, even thousands, of years of experience, herbal medicine provides an alternative to modern medicine, making healthcare more available. In fact, the majority of the worlds population uses herb products as a primary source of medicine. While some regulating authorities fear the consequences of unrestricted herbal remedy use, herbal medicine offers a degree of hope to some patients whose disease states do not respond favorably to modern pharmaceuticals. More often, however, herbal remedies are used to treat the common ailments of daily living like indigestion, sleeplessness, or the common cold.

A resurgence in interest in herbal medicine has occurred in the United States as medical experts have

begun to recognize the potential benefit of many herbal extracts. So popular has herbal medicine become that scientific clinical studies of the effectiveness and proper dosing of some herbal medicines are being investigated.

Herbal medicine recognizes the medicinal value of plants and plant structures such as roots, stems, bark, leaves, and reproductive structures like seeds and flowers. To some, herbal medicine may seem to be on the fringes of medical practice. In reality, herbal medicine has been in existence since prehistoric time and is far more prevalent in some countries than is modern healthcare. The use of herbs ground into powders, filtered into extracts, mixed into salves, and steeped into teas has provided the very foundation upon which modern medicine is derived. Indeed, herbal medicine is the history of modern medicine.

Many modern drugs are compounds that are derived from plants whose pharmacological effects on humans had been observed long before their mechanisms of action were known. A common example is aspirin. Aspirin, or acetylsalicylic acid, is a compound found in the bark of the willow tree belonging to the taxonomic genus Salix. Aspirin, now sold widely without prescription, is an effective analgesic, or pain reliever, and helps to control mild swelling and fever. While aspirin is synthetically produced today, willow bark containing aspirin was used as an herbal remedy long before chemical synthesis techniques were available. Similarly, the modern cardiac drug digitalis is derived from the leaves of the purple foxglove plant, Digitalis purpurea. Foxglove was an herbal known to affect the heart long before it was used in modern scientific medicine.

A prime example of the prevalence of herbal medicine in other cultures is traditional Chinese medicine. Herbal remedies are a central aspect of traditional Asian medical practices that have evolved from ancient societies. The philosophical and experimental background of Chinese herbal medicine was established more than two thousand years ago. Large volumes of ancient Chinese medical knowledge, largely concerning herbs, have been preserved which chronicle wisdom gathered throughout periods of history. Some of the information is dated to about 200 BC. One Chinese legend tells of how Shen Nung, an ancient Chinese emperor, tested hundreds of herbs for medical or nutritional value. Many herbs from Chinese traditional medicine have documented pharmacological activity. Ma Huang, also called Chinese ephedra, is an example. This herb, Ephedra sinica has a potent chemical within its structures called ephedrine. Ephedrine is a powerful stimulant of the sympathetic nervous system, causing widespread physiological effects such as widening of breathing passages, constriction of blood vessels, increased heart rate, and elevated blood pressure. Ephedrine, whether from Ma Huang or modern medication preparations, mimics the effects of adrenaline on the body. Modern medicine has used ephedrine to treat asthma for years. Chinese traditional herbal medicine has been using Ma Huang to treat disease for many hundreds of years.

The term alternative medicine is often used to describe treatments for disease that do not conform to modern medical practices, including herbal medicine. Alternative medicine includes things such as apitherapy, the use of bee stings to treat neurological diseases. Some use apitherapy to treat multiple sclerosis, which is a degenerative nerve disease that can cripple or blind its victims. In addition, alternative medicine includes scientifically unfounded therapies such as kinesiology (the healing properties of human touch), acupuncture, aromatherapy, meditation, massage therapy, and homeopathy.

Aromatherapy and homeopathy are closely related to herbal medicine because they both use botanical, or plant, extracts. Aromatherapy uses the strong odors from essential oils extracted from plants to induce healing and a sense of well-being. Homeopathy is the art of healing the sick by using substances capable of causing the same symptoms of a disease when administered to healthy people. Many homeopathic remedies are herbal extracts. Homeopathic medicine has been practiced for over 200 years. German physician Samuel Hahnemann (17551843) began the practice of homeopathy using herbs in 1796. The philosophy behind this form of herbal medicine is to induce the body to heal itself. The use of herbals in homeopathic treatment follows the unscientific principle of Let likes be cured by likes.

KEY TERMS

Aromatherapy The use of odorous essential oils from herbs to heal and induce feelings of well-being.

Homeopathy A system in which diluted plant, mineral, or animal substances are given to stimulate the bodys natural healing powers. Homeopathy is based upon three principles: the law of similars, the law of infinitesimal dose, and the holistic medical model.

Pharmacopoeia An official, and legal listing of approved drugs, drug manufacture standards, and use enforced by legislation.

Homeopathic remedies, and herbal remedies in general, are primarily used in alleged self-care, without the help of a physician. Because many remedies have genuine effects, the United States government regulates the homeopathic substances. The Homeopathic Pharmacopoeia of the United States (HPUS) is the official list of accepted remedies that the law uses as standard. Along with the United States Pharmacopoeia and National Formulary (USP/NF) that lists all regulated drugs and drug products, the HPUS is the legal source of information for the U.S. Federal Food, Drug, and Cosmetics Act. Standards for manufacture, purity, and sale of drugs are listed in these documents, enforced by law.

Most people are concerned that herbal medicine products that are currently widely available are a danger to public health, safety, and welfare because an official federal pharmacopoeia for herbals does not yet exist. Therefore, few legal requirements exist for the manufacture, dose standardization, labeling, and sale of preparations for herbal medicines. Yet, herbal remedies are the fastest growing segment of the supplemental health product industry. Such problems with purity and dosage only add to skepticism regarding the therapeutic value of many herbals. Many of the health claims made by advertisements have not been evaluated scientifically.

For drugs to be sold, the Food and Drug Administration (FDA) requires manufacturers to conduct lengthy studies to prove the safety and efficiency of both prescription and over-the-counter drugs. However, manufacturers of herbal medicines are held to no such rigorous standard. By placing herbal medicines in the same category as dietary supplements, like vitamins and minerals, the FDA effectively exempts them from having to be rigorously tested. Further, the 1994 Dietary Supplement Health and Education Act allows herbal manufacturers to make limited claims on their labels as long as they do not claim to diagnose, prevent, mitigate, treat or cure a specific disease.

Examples of herbal medicine products in wide use today are St. Johns wort for depression, echinacea for increased immune function, saw palmetto for prostate gland problems in men, and ginkgo biloba for improved mental functioning and headaches. Other forms of herbal medicine in popular culture include herbal teas, like chamomile tea used to help people who have trouble sleeping and peppermint tea to calm stomach and digestive problems.

Resources

BOOKS

Basch, Ethan M., and Catherine E. Ulbright, eds. Natural Standard Herb & Supplement Handbook. St. Louis, MO: Elsevier Mosby, 2005.

Ernst, Edzard, ed. The Desktop Guide to Complementary and Alternative Medicine. Edinburgh, UK, and New York: Mosby, 2001.

Foster, Steven. Desk Reference to Natures Medicine. Washington, DC: National Geographic Society, 2006.

The Merck Index: An Encyclopedia of Chemicals, Drugs, & Biologicals. 14th ed. Whitehouse Station, NJ: Merck & Co., 2006.

Moss, Donald, ed. Handbook of Mind-body Medicine for Primary Care. Thousand Oaks, CA: Sage Publications, 2003.

Nurses Handbook of Alternative & Complementary Therapies. Philadelphia, PA: Lippincott Williams & Wilkins, 2003.

Tovey, Philip, Gary Easthope, and Jon Adams, eds. The Mainstreaming of Complementary and Alternative Medicine: Studies in Social Context. London, UK, and New York: Routledge, 2004.

OTHER

Rainforest Alliance. (March 2003) <http://www.rainforestalliance.org.> (accessed March 23, 2007).

Terry Watkins

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Herbal Medicine

Herbal Medicine

Overview

Herbal or botanical medicine employs roots, leaves, and barks as drugs for the treatment of disease. The medicinal use of herbs and other botanical products is probably as old as medical treatment itself. A common belief throughout history is that nature provides plants in each region that are appropriate for the cure of local diseases. Drug collectors and healers in many cultures used "herbals"—manuals that provide guidance in the identification of medicinal plants and recipes for preparing remedies. Healers in ancient Asia, India, Mesopotamia, Greece, and Rome employed hundreds of medicinal plants. With the invention of the printing press, ancient herbals and their descendants became widely available. Even in the ancient world, the search for new medicinal herbs played an important role in exploration.

Background

In very early times, in virtually every part of the world, the most important uses of herbs and spices were medicinal, either for internal use or in ointments, balms, and poultices. Ancient herbals, including those of China, India, Sumer, Assyria, Egypt, Greece, and Rome, testify to the widespread use of spices and herbs in the treatment of disease. Herbs and spices retained their medicinal reputation throughout history; their curative virtues are still highly respected, especially in Asia and India.

Traditionally, herbal medicine employed herbs and spices, often in combination with animal parts and products and minerals. Many medicinal herbs and spices are cultivated for their aromatic, pungent, or otherwise desirable qualities. Often the important parts are dried for storage and to concentrate the valuable components. Spices and herbs consist of rhizomes, bulbs, barks, flower buds, stigmas, fruits, seeds, and leaves. Herbs are the fragrant leaves of plants such as marjoram, mint, rosemary, and thyme.

More than any other culture, China has maintained its traditional medicine, especially its rich drug lore, largely based on herbal remedies. The herbalists of China may have studied and employed as many as 5,000 plants. When Li Shih Chen (1518-1593), China's "prince of pharmacists," published his great Materia Medica (Pen ts'ao kang mu) in 1578, his scholarly compilation of Chinese herbal lore contained 1,892 drugs from the vegetable, animal, and mineral kingdoms, and more than 8,000 prescriptions. Today, Chinese scientists are attempting to isolate specific active ingredients from traditional remedies.

Shen Nung, one of the Three Celestial Emperors revered as the founders of Chinese civilization, is also known as the "Divine Peasant." Shen Nung is said to have personally tasted "the hundred herbs" so that he could teach the people which were therapeutic. His findings were allegedly recorded in the first pharmacopoeia, the Pen-ts'ao, or Great Herbal. Huang-Ti, the last of the Celestial Emperors, is considered the author of the Nei Ching, or The Yellow Emperor's Classic of Internal Medicine, a text that has inspired and guided Chinese medical thought for over 2,500 years. According to the Nei Ching, the first remedies were found among the herbs, trees, plants, and animals that served as foods. The use of tea, a beverage made from the leaves of the tea shrub, illustrates the overlap between "foods" and "drugs." Tea contains small amounts of nutrients, but it is rich in physiologically active alkaloids (caffeine, theobromine, and theophylline). The three classes of drugs—vegetable, animal, and mineral—were said to correspond to heaven, man, and earth. Animal parts and products were regarded as sources of remarkable "vital principles." Traditional remedies included seaweed and sea horse powder (good sources of iodine and iron) for goiter and chronic fatigue, and ephedra for lung diseases and asthma. Ginseng, the "queen of medicinal herbs," was credited with almost miraculous powers.

Medical therapy can take two general forms: doctors can try to strengthen the body so that it can heal and defend itself, or they can attack the agents of disease directly. The primary goal of Chinese herbal medicine was to strengthen and protect the body, restore its normal balance of energy, and promote longevity. Ginseng exemplifies the classical Chinese approach to healing. It has been used as a tonic, a rejuvenator, and an aphrodisiac. Modern researchers have called it an "adaptogen," a substance that increases resistance to all forms of stress, from disease to misfortune. Many other cultures have adopted similar ideas about herbal remedies.

Impact

Like Chinese medicine, Indian medicine attempted to prolong life, preserve health, and prevent disease. Ayurveda, the learned system that forms the basis of the traditional medicine that is still widely practiced in India today, is known as "the science of life." Herbal medicines and dietary regulations are of special importance in Ayurvedic medicine.

The richly diverse flora and fauna of India provided a wealth of medicinal substances. Almost 1,000 medicinal herbs are referred to in the major medical classics of ancient Indian civilization, but many are unidentifiable materials or "divine drugs" such as "soma." Although plants provided the majority of medicinal substances, minerals and animal products, such as honey, milk, snake skin, and excrements, are also well represented. Because of the importance of using ingredients that were pure and unadulterated, and herbs that were harvested at auspicious times, the wise physician compounded his own drugs from ingredients that he had gathered himself.

Unlike the learned medical systems of China and India, those of ancient Mesopotamia are no longer extant, but ancient drug lore was not entirely lost. Many civilizations, including those known as Sumerian, Chaldean, Assyrian, and Babylonian, once flourished in Mesopotamia, the land between the Tigris and Euphrates Rivers in modern Iraq. One of the oldest known pharmaceutical documents is a clay tablet probably inscribed about 4,000 years ago by a Sumerian scholar. The tablet contains a series of drug formulas and suggests considerable knowledge of many medicinal herbs and minerals. Plants and herbs were so important to ancient medicine that the terms for "medicine" and "herbs" were essentially equivalent. The ancient civilizations of Mesopotamia developed a very comprehensive materia medica. Scholars who studied clay tablets from ancient Assyria have identified about 250 vegetable drugs and 120 mineral drugs, as well as alcoholic beverages, fats and oils, parts of animals, honey, wax, and various milks thought to have special medicinal virtues. Botanical drugs included asafetida, cannabis, crocus, hellebore, mandragora, myrrh, opium, pine turpentine, and so forth. Drugs made from seeds, bark, and other parts of plants were dissolved in beer or milk and administered by mouth, or mixed with wine, honey, and fats and applied externally. The sources used by the herbalist were essentially those typical of folk medicine, but Mesopotamian pharmaceutical texts reflect familiarity with fairly elaborate chemical operations for the purification of basic ingredients. Purgative remedies are very prominent in the medical tradition of Mesopotamian civilizations because illness was regarded as a divine punishment for sins committed by the patient. Healing, therefore, required both physical and spiritual catharsis, or purification. The status of the herbalist seems to have deteriorated as Mesopotamian civilizations became more interested in the magical approach to healing.

Greek writers like Homer (ninth to eighth century? b.c.), Herodotus (484-430/420? b.c.), and Theophrastus (372?-287? b.c.) praised the physicians of Egypt for their wisdom and skill and took note of the valuable medicinal plants they prescribed. Unfortunately, only a few fragmentary medical papyri, which were probably composed between about 1900 and 1100 b.c., have survived. The medical papyri provide information about ancient Egyptian ideas about health and disease, anatomy and physiology, magic and medicine, in the form of case histories, remedies, drug formularies, recipes, and incantations. The most complete and famous is known as the Ebers papyrus. Written about 1500 b.c., the Ebers papyrus includes an extensive collection of prescriptions, as well as incantations and extracts of medical texts on diseases and surgery. About 700 drugs, made up into more than 800 formulas, are found in the Ebers papyrus. Many recipes call for incomprehensible, exotic, or seemingly impossible ingredients, which may have been secret or picturesque names for various plants. Physicians apparently relied on specialized assistants and drug collectors, but sometimes they prepared their own remedies. In contrast to Mesopotamian custom, Egyptian prescriptions were precise about quantities. Although the Egyptians were familiar with the sedative effects of opium and henbane, there is no direct evidence that they were used as surgical anesthetics.

In 332 b.c. Alexander the Great (356-323 b.c.) conquered Egypt and brought it into the sphere of Hellenistic culture. How much the Greeks learned from the Egyptians and how much they taught them is difficult to determine, but Greek physicians adopted many of Egyptian drugs. Hippocrates (460?-377? b.c.), Dioscorides (40?-90?), Galen (129-199?), and many other Greek physicians prescribed herbal remedies.

Theophrastus of Eresus (390-286 b.c.), a Greek philosopher who studied with Plato (427?-347 b.c.) and Aristotle (384-322 b.c.), is credited with founding botany. Theophrastus became one of Aristotle's favorite disciples and inherited his library. Thus the writings of Theophrastus provide important insights into the botanical teachings of Aristotle, who left no botanical works of his own. De historia plantarum, the most important surviving work by Theophrastus, includes important information about plant lore and gathering herbs for medicinal purposes. Theophrastus collected and organized the existing botanical knowledge of his time and described about 500 plants. Theophrastus classified plants as trees, shrubs, and herbs. His basic concepts of morphology, classification, and the natural history of plants were accepted without question for many centuries.

The Greek physician Crateuas (first century b.c.) composed the earliest known illustrated herbal. The text classified plants and discussed their medicinal uses. Unfortunately, only fragments of the works of Crateuas have survived, generally as extracts in the works of other writers.

From the second century b.c. to the first century a.d., a succession of Roman writers prepared Latin treatises on farming, gardening, and fruit growing. Although these Roman collections were not scientific, they do provide information about the plants that practical Romans considered most valuable. Pliny the Elder (23-79) compiled an encyclopedia known as the Historia naturalis (Natural history). Sixteen of its 37 volumes were devoted to plants. Pliny had high praise for the healing powers of many herbs and spices. The Historia naturalis is valuable as a compilation of some 2,000 works representing 146 Roman and 327 Greek authors. Although Pliny was rather uncritical in assembling his materials, his encyclopedia preserved excepts of many texts that would otherwise be totally lost. A work composed in a.d. 47 by Scribonius Largus (fl. a.d. 40) provides a compilation of drugs and prescriptions, as well as the first accurate description of the preparation of true opium.

The Greek physician and pharmacologist Dioscorides wrote a more systematic treatment of herbal medicine. Dioscorides is considered the originator of European materia medica. His De materia medica was the most important source of herbal lore and pharmacology for almost 16 centuries. Many of the drugs described by Dioscorides were still commonly used in medical practice. Dioscorides's travels as a surgeon with the armies of the Roman emperor Nero provided him an opportunity to study the features, distribution, and medicinal properties of many plants and minerals. The text refers to approximately 1,000 simple drugs. De materia medica includes descriptions of nearly 600 plants, including cannabis, colchicum, water hemlock, and peppermint and refers to sleeping potions prepared from opium and mandragora as surgical anesthetics. It is interesting to note that Dioscorides called attention to the Egyptian origins of about 80 of the vegetable drugs described in his herbal. Dioscorides grouped his plants under three headings: aromatic, culinary, and medicinal. He also discusses the medicinal and dietetic value of various animal parts and products, such as milk and honey, and the medicinal use of minerals, including mercury, arsenic, lead acetate, calcium hydrate, and copper oxide. An illustrated Byzantine version of Dioscorides's famous herbal, known as the Constantinopolitan Codex was prepared in the sixth century a.d. Some of its illustrations and plant names are probably derived from Crateuas.

Many manuscript herbals, drawing largely from Dioscorides and Pliny, were reproduced in medieval Europe. The printing press revolutionized the availability of all types of literature, including that of medicine and pharmacology. Many herbals were published in the fifteenth and sixteenth centuries. Written by physicians and botanists, the earliest printed herbals were generally derived from the work of Dioscorides and Theophrastus. Traditional herbal medicine is practiced in much of the world today, especially in Asia and India, and herbs still play a role in Western medicine. Present-day herbalists extol the efficacy of herbs, spices, and spice seeds in the treatment of certain ailments and argue that herbs are far less likely to cause dangerous side-effects than prescription drugs.

LOIS N. MAGNER

Further Reading

Anderson, Frank J. An Illustrated History of the Herbals. New York: Columbia University Press, 1997.

Arber, Agnes Robertson. Herbals: Their Origin and Evolution. A Chapter in the History of Botany, 1470-1670. 3rd ed. Cambridge: Cambridge University Press, 1986.

Bensky, Dan, Andrew Gamble, and Ted J. Kaptchuk. Chinese Herbal Medicine: Materia Medica. Seattle, WA: Eastland Press, 1986.

Chatterjee, Asima, and Pakrashi, Satyesh Chandra, eds. The Treatise on Indian Medicinal Plants. New Delhi: Publications & Information Directorate, 1991.

Grieve, Maud. A Modern Herbal; the Medicinal, Culinary, Cosmetic and Economic Properties, Cultivation and Folklore of Herbs, Grasses, Fungi, Shrubs & Trees, with All Their Modern Scientific Uses. New York: Hafner, 1959.

Huang, Kee Chang. The Pharmacology of Chinese Herbs. Boca Raton, FL: CRC Press, 1993.

Kapoor, L.D. CRC Handbook of Ayurvedic Medicinal Plants. Boca Raton, FL: CRC Press, 1990.

Leung, Albert Y. Chinese Herbal Remedies. New York: Universe Books, 1984.

Sivarajan, V.V., and Indira Balachandran. Ayurvedic Drugs and Their Plant Sources. New Delhi: Oxford & IBH, 1994.

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Herbal Medicine

Herbal medicine

Modern medicine has provided many breakthrough treatments for serious diseases. Some conditions, however, have eluded the healing grasp of contemporary western medicine, which emphasizes rigorous scientific investigation of therapies. In addition, rising costs of some treatments have placed modern healthcare beyond the reach of many. The drugs that routinely fill pharmacy shelves of post-industrialized nations remain inaccessible to the majority of the people in the world. Instead, populations in many areas of the globe use herbal medicine, also called botanical medicine or phytotherapy, as the principal means of healthcare. Herbal medicine is the use of natural plant substances to treat illness. Based upon hundreds, even thousands of years of experience, herbal medicine provides an alternative to modern medicine, making healthcare more available. In fact, the majority of the world's population uses herb products as a primary source of medicine. While some regulating authorities fear the consequences of unrestricted herbal remedy use, herbal medicine offers a degree of hope to some patients whose disease states do not respond favorably to modern pharmaceuticals. More often, however, herbal remedies are used to treat the common ailments of daily living like indigestion, sleeplessness, or the common cold. A resurgence in interest in herbal medicine has occurred in the United States as medical experts have begun to recognize the potential benefit of many herbal extracts. So popular has herbal medicine become that scientific clinical studies of the effectiveness and proper dosing of some herbal medicines are being investigated.

Herbal medicine recognizes the medicinal value of plants and plant structures such as roots, stems, bark , leaves, and reproductive structures like seeds and flowers. To some, herbal medicine may seem to be on the fringes of medical practice. In reality, herbal medicine has been in existence since prehistoric time and is far more prevalent in some countries than is modern health-care. The use of herbs ground into powders, filtered into extracts, mixed into salves, and steeped into teas has provided the very foundation upon which modern medicine is derived. Indeed, herbal medicine is the history of modern medicine. Many modern drugs are compounds that are derived from plants whose pharmacological effects on humans had been observed long before their mechanisms of action were known. A common example is aspirin. Aspirin, or acetylsalicylic acid , is a compound found in the bark of the willow tree belonging to the taxonomic genus Salix. Aspirin, now sold widely without prescription, is an effective analgesic, or pain reliever, and helps to control mild swelling and fever. While aspirin is synthetically produced today, willow bark containing aspirin was used as an herbal remedy long before chemical synthesis techniques were available. Similarly, the modern cardiac drug digitalis is derived from the leaves of the purple foxglove plant, Digitalis purpurea. Foxglove was an herbal known to affect the heart long before it was used in modern scientific medicine.

A prime example of the prevalence of herbal medicine in other cultures is traditional Chinese medicine. Herbal remedies are a central aspect of traditional Asian medical practices that have evolved from ancient societies. The philosophical and experimental background of Chinese herbal medicine was established more than two thousand years ago. Large volumes of ancient Chinese medical knowledge, largely concerning herbs, have been preserved which chronicle wisdom gathered throughout periods of history. Some of the information is dated to about 200 b.c. One Chinese legend tells of how Shen Nung, the ancient Chinese father of agriculture, tested hundreds of herbs for medical or nutritional value. Many herbs from Chinese traditional medicine have documented pharmacological activity. Ma Huang, also called Chinese ephedra, is an example. This herb, Ephedra sinica has a potent chemical within its structures called ephedrine. Ephedrine is a powerful stimulant of the sympathetic nervous system , causing widespread physiological effects such as widening of breathing passages, constriction of blood vessels, increased heart rate , and elevated blood pressure . Ephedrine, whether from Ma Huang or modern medication preparations, mimics the effects of adrenaline on the body. Modern medicine has used ephedrine to treat asthma for years. Chinese traditional herbal medicine has been using Ma Huang to treat disease for many hundreds of years.

The term alternative medicine is often used to describe treatments for disease that do not conform to modern medical practices, including herbal medicine. Alternative medicine includes things such as apitherapy, the use of bee stings to treat neurological diseases. Apitherapy is used by some to treat multiple sclerosis, a degenerative nerve disease that can cripple or blind its victims. Also, alternative medicine includes scientifically unfounded therapies such as kinesiology (the healing properties of human touch ), acupuncture , aromatherapy, meditation, massage therapy, and homeopathy. Aromatherapy and homeopathy are closely related to herbal medicine because they both use botanical, or plant, extracts. Aromatherapy uses the strong odors from essential oils extracted from plants to induce healing and a sense of well being. Homeopathy is the art of healing the sick by using substances capable of causing the same symptoms of a disease when administered to healthy people. Many homeopathic remedies are herbal extracts. Homeopathic medicine has been practiced for over 200 years. The German physician, Samuel Hahnemann, began the practice of homeopathy using herbs in 1796. The philosophy behind this form of herbal medicine is to induce the body to heal itself. The use of herbals in homeopathic treatment follows the unscientific principle of "Let likes be cured by likes."

Homeopathic remedies, and herbal remedies in general, are primarily used in alleged self-care, without the help of a physician. Because many remedies have genuine effects, the United States government regulates the sale of homeopathic substances. The Homeopathic Pharmacopoeia of the United States (HPUS) is the official list of accepted remedies that the law uses as standard. Along with the United States Pharmacopoeia and National Formulary (USP/NF) that lists all regulated drugs and drug products, the HPUS is the legal source of information for the Federal Food, Drug, and Cosmetics Act. Standards for manufacture, purity, and sale of drugs are listed in these documents, enforced by law. Many people are concerned that herbal medicine products that are currently widely available are a danger to public health, safety, and welfare because an official federal pharmacopoeia for herbals does not yet exist. Therefore, few legal requirements exist for the manufacture, dose standardization, labeling, and sale of preparations for herbal medicines. Yet, herbal remedies are the fastest growing segment of the supplemental health product industry. Such problems with purity and dosage only add to skepticism regarding the therapeutic value of many herbals. Most of the health claims made by advertisements have not been evaluated scientifically.

Examples of herbal medicine products in wide use today are St. Johns Wort for depression , Echinacea for increased immune function, Saw Palmetto for prostate gland problems in men, and ginkgo biloba for improved mental functioning and headaches. Other forms of herbal medicine in popular culture include herbal teas, like Chamomile tea used to help people who have trouble sleeping and peppermint tea to calm stomach and digestive problems.


Resources

books

Barney, D. Paul. Clinical Applications of Herbal Medicine. Woodland Publishing, 1996.

O'Neil, Maryadele J. Merck Index: An Encyclopedia of Chemicals, Drugs, & Biologicals. 13th ed. Whitehouse Station, NJ: Merck & Co., 2001.

Selby, Anna. The Ancient and Healing Art of Chinese Herbalism. Ulysses Press, 1998.

Sravesh, Amira A. The Alchemy of Health: Herbal Medicine and Herbal Aromatherapy. Amira Alchemy, 1998.

Taylor, Leslie. Herbal Secrets of the Rainforest: Over 50 Powerful Herbs and Their Medicinal Uses. Rocklin, CA: Prima Publishing, 1998.

Wood, Matthew. The Book of Herbal Wisdom: Using Plants asMedicine. North Atlantic Books, 1997.

organizations

Rainforest Alliance. <http://www.rainforest-alliance.org> (March 2003).

Terry Watkins

KEY TERMS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Aromatherapy

—The use of odorous essential oils from herbs to heal and induce feelings of wellbeing.

Homeopathy

—A system in which diluted plant, mineral, or animal substances are given to stimulate the body's natural healing powers. Homeopathy is based upon three principles: the law of similars, the law of infinitesimal dose, and the holistic medical model.

Pharmacopoeia

—An official, and legal listing of approved drugs, drug manufacture standards, and use enforced by legislation.

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