Contemporary medical care is filled with new and exciting technologies and approaches. Reports of great advances in our understanding of illness and its treatment appear in scientific journals, newspapers, and other media on a weekly, and sometimes daily, basis. From time to time, reports also appear about the empty pipelines in drug discovery programs, when expectations fueled by modern technology have not been met. Yet many of these programs overlook a rich source of potential therapies — the plant world.
What role could nature, specifically plants, play in contemporary medicine? Some write about the obsolescence and dangers of using plants in healing, while others suggest that the “well” of plants that could be used to improve both health care and the outcomes of disease is far from dry. James S. Miller, PhD, noted in a recent issue of the journal Economic Botany that 135 pharmaceutical drugs have been discovered from plants to date and, based on his analysis of the world’s flora and conservative historic drug discovery rates, he projects that at least 500 more pharmaceutical drugs remain to be discovered.
Delaying the progress toward improved health-care options and outcomes is the fact that as many as 70,000 plant species have yet to be discovered and, because of habitat destruction and other consequences of global change, many species could disappear before they are identified and evaluated for their chemical composition and medicinal potential.
Here are a few facts to consider. As Dr. Miller points out, many of our most important prescription pharmaceuticals are based on single compounds derived from plants. For example, the compound vincristine, derived from the rosy periwinkle (Catharanthus roseus) and approved for use by the FDA in 1963, is used to treat the 3,800 new cases of childhood leukemia diagnosed annually in the United States. It has an impressive record of up to 90-percent remission, based on the type of cancer and age of the patient. A relatively recent example of a whole plant extract being developed as an effective pharmaceutical is from a plant familiar to all — tea (Camellia sinensis).
In 2006, the FDA approved the prescription use of a topical preparation of tea extract for the treatment of perianal and genital condyloma (warts). When applied as an ointment, Veregen, as this pharmaceutical is called, completely resolved these conditions in 54 percent of patients who used it.
Many herbal remedies prepared as whole-plant extracts and sold as supplements, tinctures, or teas are being incorporated into Western health care through the field of integrative medicine, which is now taught at more than 50 academic medical centers and affiliate institutions in the United States alone. Clinical and preclinical research of these plants and their compounds is underway, and those herbs and formulations with convincing evidence of safety and efficacy will continue to find their way into Western medical care.
Meanwhile, much of the developing world still depends on plants to treat many primary health-care conditions — ranging from respiratory infections, wounds, and colds to diarrheal diseases that could otherwise prove fatal. Nature is the medicine chest for billions of people, and many generations of their traditional healers — the equivalent of our Western physicians — have already carried out human clinical trials.
It turns out that Mother Nature is a brilliant chemist. Hundreds of thousands of compounds have been identified from plants. Some of these are used in prescription pharmaceuticals, others in botanical supplements, and many more remain to be discovered.