Medicinal plants--old and new.

The historic role of plants in healing declined early in the twentieth century with the ascendency of synthetic drugs, even though a number of basic medical tools, such as opium, strychnine, and cocaine, are of botanical origin. In recent years, interest in natural products has been restored dramatically by the discovery of penicillin, plant-derived tranquilizers, and plant precursors of cortisone. Contrary to previous beliefs, botanical drugs are proving more economical than synthetics and hold forth encouraging prospects of inhibiting or destroying tumors without undue damage to healthy tissue. Extensive plant screening programs are being conducted by governmental agencies and pharmaceutical houses. Folk remedies, still common in many tropical areas, are being evaluated. As a result of such research by Canadian and American scientists, alkaloids extracted from the Madagascar periwinkle (Vinca rosea) are being effectively employed to achieve regression in childhood leukemia. Potentially more rewarding are investigations of compounds obtained from the Australian tree, Acronychia baueri and a Chinese species, Camptotheca acuminata. Universities are reestablishing medicinal plant gardens and placing more emphasis on pharmacognosy. Experimental work with narcotic plants in psychiatric treatment has given rise to popular fascination with and abuse of certain natural hallucinogens. Among scientists engaged in chemical studies, there is an active demand for information about plants, their properties and therapeutic uses. Even the general public is being made aware that plant drugs are not obsolete but offer new hope for conquering disease.