Chemists in Taiwan are reporting that an ingredient in licorice
— widely used in various foods and herbal medicines — appears to
block the absorption of cyclosporine, a drug used by transplant
patients to prevent organ rejection. This drug interaction could
potentially result in transplant rejection, causing illness and
even death among patients worldwide who take cyclosporine and
licorice together, the researchers caution. The study is the
first report of this potential drug interaction, the scientists
say. Their findings will be presented here today at the American
Chemical Society's 237th National Meeting. "I would suggest that
transplant patients avoid taking licorice," warns Pei-Dawn Lee
Chao, Ph.D., a chemist at China Medical University in Taichung,
Taiwan. The researchers say they do not know exactly how much
licorice it takes to have a toxic effect in humans. Since
licorice-based products vary widely in their content of its main
active ingredient, a substance called glycyrrhizin, Chao
suggests that pa