Bloodroot (Sanguinaria canadensis) was used by Native Americans to treat fevers and rheumatism and to induce vomiting. Modern herbalists use it as an emetic too, as well as to promote coughing and clearing of the respiratory tract. They also use it cautiously because bloodroot can be toxic in large doses.
Pacific yew (Taxus brevifolia) grows in the Cascade Range running from Washington to Northern California. It was once used to treat rheumatism, but modern herbalists avoid yew because it is extremely toxic.
In the 1960s, National Cancer Institute researchers began examining an extract from the yew’s inner bark, thinking it held potential as a cancer treatment. By the late 1970s, they isolated Taxol from the yew extract. Taxol stops the division of cells, including cancerous ones. In 1989, the results of a trial of Taxol taken by women with ovarian cancer showed that 30 percent of the patients improved, and the Food and Drug Administration approved Taxol’s use as a drug in 1993.
While the Pacific yew is the main source of Taxol, researchers have devised a process to manufacture Taxol from other yew species as well.
Wild yam (Dioscorea villosa) is native to North and Central America. The Mayans and Aztecs used it to relieve pain, and North American pioneers used it to treat rheumatism. These cultures also used wild yam to treat painful menstruation and labor pains.
Today, we know that wild yam roots and tubers contain plant sterols, specifically diosgenin, which, when synthesized, provides progesterone.
Click here for the original article, The Origins of Plant Medicine .