Category:Herbal medicine

Medicinal herbs

Herbal medicine -- also called botanical medicine or phytomedicine -- refers to using a plant's seeds, berries, roots, leaves, bark, or flowers for medicinal purposes. Herbalism has a long tradition of use outside of conventional medicine. It is becoming more mainstream as improvements in analysis and quality control along with advances in clinical research show the value of herbal medicine in the treating and preventing disease.

Tradition of Herbal Medicine

In the written record, the study of herbs dates back over 5,000 years to the Sumerians, who created clay tablets with lists of hundreds of medicinal plants. The largest surviving such medical treatise from ancient Mesopotamia is known as "Treatise of Medical Diagnosis and Prognoses." The text of this treatise consists of 40 tablets collected and studied by the French scholar R. Labat. Although the oldest surviving copy of this treatise dates to around 1,600 BC, the information contained in the text is an amalgamation of several centuries of Mesopotamian medical knowledge. It has been shown that the plants used in treatment were generally used to treat the symptoms of the disease, and were not the sorts of things generally given for magical purposes. The same plants were used then as are today. At the same time in Egypt, (c. 1,500 BC), the Ancient Egyptians wrote the Ebers Papyrus (right) which contains information on over 850 plant medicines, including garlic, juniper, cannabis, aloe, and mandrake.
In India, the Rig-Veda a sacred Hindu text lists herbal medicines and created the Ayurvedic health care system in this Asia country. Ancient China has its own list of herbal medicines compiled in the Pun-tsao text, written in the 1600s. In the New World, the Aztecs wrote texts on herbal medicines derived from their knowledge of plants they had discovered to have medicinal qualities. The Badianus Manuscripts were written in 1592 by the Aztec Martinus de la Cruz for King Charles I of Spain.
Indigenous cultures (such as African and Native American) used herbs in their healing rituals, while others developed traditional medical systems (such as Ayurveda and Traditional Chinese Medicine) in which herbal therapies were used. Researchers found that people in different parts of the world tended to use the same or similar plants for the same purposes.
In ancient Greece, Hippocrates sought herbal remedies as cures for illness and disease. Another Greek named Dioscorides collected plants during his travels with the Roman army and investigated whether they had any medicinal value. His work De Materia Medica listed 600 species of plants that had some sort of medicinal quality. The Age of Herbals, which began in 1450, brought about a revival in using plants for medicinal purposes. Authors such as John Gerard and John Parkinson wrote about the benefits of plants for medicinal purposes. Nicholas Culpepper wrote about the Doctrine of Signatures which stated that the designs or colors of a plants corresponds to human anatomy.

Modern Herbal Medecine

Today, many rural populations in the world use plants for medicinal purposes. Medicinal plants offer poorer populations the ability to combat diseases at low costs. Countries like China and India continue to teach their medical students how to use plants in order to make proven and effective medicines for their patients. Many conventional drugs originate from plant sources: a century ago, most of the few effective drugs were plant-based. Examples include aspirin (from willow bark), digoxin (from foxglove), quinine (from cinchona bark), and morphine (from the opium poppy). The development of drugs from plants continues, with drug companies engaged in large-scale pharmacologic screening of herbs. Modern Western herbalism emphasizes the effects of herbs on individual body systems. For example, herbs may be used for their supposed anti-inflammatory, hemostatic, expectorant, antispasmodic, or immunostimulatory properties. Consumer spending on herbal products in the United States is estimated to be more than $5 billion per year, mainly from self-prescription of over-the-counter products. This type of herbal drug use is typically based on a simple matching of a particular herb to particular diseases or symptoms—such as valerian (Valeriana officinalis) for sleep disturbance. Originally confined to health food shops, herbal remedies are now marketed in many conventional pharmacies and retail stores.

Differences from conventional drug use

Although superficially similar, herbal medicine and conventional pharmacotherapy have important differences.

• Use of whole plants : Practitioners of herbal medicine generally use unpurified plant extracts containing several different constituents. Typically, they claim that these can work together synergistically so that the effect of the whole herb is greater than the sum total of the effects of its components. They also claim that toxicity is reduced when whole herbs are used instead of isolated active ingredients (“buffering”). Although 2 samples of a particular herbal drug may contain constituent compounds in different proportions, practitioners claim that this does not generally cause clinical problems. Some experiments have yielded evidence of synergy and buffering in certain whole plant preparations, but how far this is generalizable to all herbal products is not known.
• Herb combining : Several different herbs often are used together. Practitioners say that the principles of synergy and buffering apply to combinations of plants and claim that combining herbs improves efficacy and reduces adverse effects. Herb combining contrasts with conventional practice, in which polypharmacy is generally avoided whenever possible.
• Diagnosis : Herbal practitioners use diagnostic principles that differ from those used by conventional practitioners. For example, when treating arthritis, herbal practitioners might observe “underfunctioning of a patient's systems of elimination” and decide that the arthritis results from “an accumulation of metabolic waste products.” A diuretic, choleretic, or laxative combination of herbs might then be prescribed alongside herbs with anti-inflammatory properties.

References

West J Med. 2001 August; 175(2): 125–128