"New" Drugs, Ancient Uses; What Chemists Can Learn From The Past

Dr. John Riddle, professor of history at NC State and an expert on the historic use of medicines derived from plants, will present his findings today, March 30, at the 219th American Chemical Society (ACS) Annual Meeting in San Francisco.

He says a greater knowledge of, and critical appreciation for, ancient medicine could provide modern doctors with alternative ways of treating diseases, and help them identify and label potential dangers and side effects from "new" drugs and herbal supplements.

He points to St. John’s wort, one of the most popular herbal supplements used today, as an example.

Though now most commonly taken for depression, St. John’s wort was first used in 800 A.D. as an antiseptic to treat wounds and as a treatment for bladder problems. Riddle’s studies revealed that it also sometimes caused miscarriages; in fact, ancient literature makes several references to the herb’s abortifacient effects. However, none of this was mentioned in modern literature about St. John’s wort prior to 1998. Based on Riddle’s research, manufacturers began labeling their bottles, warning pregnant women not to take the supplement.

"No one believes that the pre-modern world could possibly have any insight into science that modern science doesn’t already know," says Riddle, whose ACS presentation closely examines the historic use of botanicals -- plant-derived medicines -- that affect the endocrine system. Learning how a botanical was used in the past could give pharmaceutical chemists important clues about its unforeseen side effects and alternative uses, he says. "Yet I don’t know of any chemists who begin a study with (a review of) the history of a compound."

Retrospective discovery can be a useful tool, Riddle believes, because although new drugs are tested for short-term safety for a prescribed use, drugs used as folk medicine over a long time can provide a living laboratory about safety and efficacy, often for various uses.

The drug Finasteride is a case in point. It was initially marketed by Merck under the brand name Proscar as a treatment for prostate problems in older men. When the company discovered, after more research, that Finasteride also promoted hair growth in men, it lowered the dosage and began marketing the drug as Propecia.

"A similar compound is freely available in saw palmetto and nettle," Riddle says. "The ancients took it for urinary problems and to promote hair growth. So Merck need not have done all that research." They could have told from reviewing the drug’s history that the compound has alternative uses.

The stories of Propecia and St. John’s wort demonstrate how Western culture has turned its back on ancient medicine, Riddle says. He places some of the blame on the development of universities as the centers for institutional learning. "The academic community disdained folk knowledge and would not incorporate its learning within its body of things to know," he says. Chinese and Islamic cultures, Riddle adds, never developed this distrust.

The American Chemical Society is a nonprofit scientific and educational organization made up of nearly 159,000 chemists and chemical engineers around the world.