It is likely that all cultural groups have used plants as therapeutic agents since prehistoric times. China and India have recorded descriptions of medicinal plants as early as 2700 B.C. Egyptian, Greek, Roman, and Arab physicians described medicinal properties of plants. Indigenous people of Central America, South America, North America, and Africa have further contributed to the knowledge of medicinal plants.
Research led to the isolation and characterization of the active principles of many botanical medicines now manufactured or isolated by pharmaceutical firms. Among them are morphine (from poppy); reserpine (a tranquilizer from snakeroot); curare (a muscle relaxant from the curare vine); quinine (the first malarial treatment, from the bark of the cinchona tree); digitalis (heart stimulant from foxglove); atropine (pupil-dilating drug from deadly nightshade); and others. Medicinal plants are currently being screened for anticancer and antiviral constituents on which to base new drugs. With the appearance of antibiotic-resistant bacteria, medicinal plants offer the promise of new treatment.
A set of terms describing the use of plant remedies and ailments for which they are employed predates pharmacology. The following is a brief description of key terms used in botanical medicine.
Relieve pain. Examples include hops and wintergreen.
Contract certain tissues and decrease mucous discharge. Examples include bayberry; blackberry; witch hazel.
Relieve constipation. Examples include chicory, dandelion.
Oily or mucilaginous materials that soothe digestive upsets. Examples include borage, chamomile, ginger root, sassafras.
Induce sweating. Examples include borage, chamomile, ginger root, sassafras.
Induce frequent urination. Examples include alfalfa, buchu leaves, celery, chicory, corn silk, dandelion, horehound, parsley (root), wild carrot.
Antipyretics that lower body temperature during episodes of fever. Examples include angelica, balm, borage, dandelion.
Examples include angelica, bayberry leaves, capsicum, cardamom, sarsaparilla root, wintergreen.
There are several caveats in using medicinal plants:
• A number of plant species may be harmful (such as comfrey, lobelia, sassafras root).
• Allergic reactions may occur in susceptible people.
• Safe and adequate doses depend on many variables. Often it is difficult to standardize herbal preparations because of variation in harvesting, storage, and growth conditions. Furthermore, doses tolerated in adults may be harmful to children.
• Often claims like “blood purifier” are used without definition. Professional medical advice is prudent for any chronic symptoms.