Glossary

Phytomedicine

Phytomedicine is the study and practice of using plant materials for medicine and health promotion. An herb can be an angiosperm (a flowering plant, shrub, or tree, a moss, lichen, fern, algae, seaweed, or fungus). The herbalist may use the entire plant, or specifically the flowers, fruits, leaves, twigs, bark, roots, rhizomes, seeds, exudates (such as tapped and purified maple syrup), or a combination of parts. A variety of forms of delivery of herbal medicines are known. Some plants are best used fresh. Dried, whole, or chopped herbs can be prepared as infusions (steeped as tea) or decoctions (simmered over a low heat). Flowers, leaves, and powdered herbs are infused. Fruits, seeds, bark, and roots require decocting. Many fresh and dried herbs can be tinctured as preserved medicines in alcohol; some plants are suited as acetracts (vinegar extracts). Others are active and well-preserved as syrups. Powdered and freeze dried herbs are available in bulk, tablets, troches, pastes, or capsules. Non-oral delivery forms include creams, ointments, gels, oils, bath, compresses, steams and inhaled smokes and aromatics (volatile oils). The predominant plant delivery forms vary among different herbal traditions. Phytotherapy is a broad term: there is no single system of phytomedicine (Phytotherapy). The use of plants and their properties are specific to each society and paradigm. Herbal medicine can be broadly classified into four basic systems as follows: Traditional Chinese Medicine, Ayurvedic Herbalism, Western Herbalism (which originally came from Greece and Rome, thence to Europe) spread to North and South America.  Traditional Arabic Islamic Medicine also exists. In Chinese and Tibetan medicine, the “five tastes” are sweet, sour, salty, pungent, and bitter. Each flavor is associated with certain qualities and corresponding physiologic actions. In many traditional systems, the characteristics of a medicinal plant are emphasized without attention to its composition because techniques and equipment for plant analysis are new.  Knowledge has been derived from direct perception through the senses and from empirical observation of plants’ effects on animals and human. In Europe and United States, physicians relied on plant drugs as primary medicines through the 1930’s. Until that time, medical schools taught basic plant taxonomy, pharmacognosy, and medicinal plant therapeutics. Since then, the pharmaceuticals have dominated the health market. Medicinal plants have multiple actions due at least, in part, to their multiple constituents. This is in relative contrast to many pharmaceuticals which typically have a single or a few specific therapeutic actions. The vast majority of medicinal plants are much less potent than pharmaceuticals. It has been argued that since humans have evolved on plant based diets, humans are probably better adapted to plants as food and medicine than to strong pharmaceutical drugs. Knowledge of the chemical composition of medicinal plants is growing worldwide as access to analytical technology improves. Perhaps, the disadvantage to identifying, categorizing, and researching molecular constituents from plants is the risk of equating the plant’s therapeutic efficacy to its composition according to the reductionism paradigm.