Although Native Americans have long sought pain relief by drinking a tea made from the bark of the willow, scientists did not learn until much later that the bark contained salicylic acid, which is the active ingredient in aspirin. The field of medicine is discovering that many such folk remedies may be based on more than myth. There are thousands of plant species which remain to be studied for their potential to cure disease.
Plants in Ancient Medicine
There is evidence that the Babylonians were importing myrrh for use as medicine as early as 3000 B.C. Medicinal plants are mentioned in ancient writings from China and India. The early Greek physician Hippocrates and the Roman physician Galen used plants as medicine and had plants named after them. Carolus Linnaeus, the famous Swedish botanist, was a physician, since as late as the 19th century, having knowledge of plants was viewed as an essential part of medicine.
Every society or tribe has had members who served as the dispensers of medicine. The knowledge of these medicine men and women, or shamans, was powerful and often connected to a culture's religion. Use of plants by shamans for hallucinogenic purposes can be dated as far back as 10,000 years. In every region, the medical uses of plants was probably determined by observation and experimentation, and then passed on to future generations by word of mouth, becoming ethnopharmacology, or folk medicine.
An important medical role of plants was their antiseptic nature. In ancient Egypt, knowledge of spices mixed with resins and natron was used to perfect the technique of mummification. Plants were also powerful infection fighters, with willow and quinine serving as antipyretics (fever reducers). Plants which contain alkaloids, such as the coca and poppy plants, served as pain-relievers and were the earliest anesthetics for operations. Many medicinal plants required very careful use, since the same plant might serve as medicine, drug or poison. One concentration may cure disease, while another may cause it to become an addictive substance, and a yet stronger concentration can become a toxic or fatal poison.
By a World Health Organization estimate, 80 percent of those living in developing countries rely on traditional medicine for their health needs, and 85 percent of traditional treatments are based on plants. For the past 25 years, one quarter of all prescriptions used by American consumers contain chemicals extracted from plants, says Norman R. Farnsworth, Professor of Pharmacognosy at the University of Illinois at Chicago. Some 175 native North American plants, such as goldenseal and ginseng, are collected in the wild in large quantities and sold as non-prescription herbal medicine. Herbal remedies are used by more than 60 million Americans.
Finding New Medicines
According to the Medicinal Plant Working Group (part of the U.S. government's Plant Conservation Alliance), if it were not for plants, most of our medicines would not exist. Scientists and chemists are continually searching for plant substances which may lead to medical cures and breakthroughs. The 1975 discovery of taxol in the Pacific yew led to the creation of a powerful tumor-fighting drugs which have helped patients with cancers of the breast and prostate. Only a small percentage of the earth's 250,000 different plant species have been exhaustively searched for their medical potential.